Correlation does not imply causation

From Wikipedia, the free encyclopedia

In statistics, the phrase "correlation does not imply causation" refers to the inability to legitimately deduce a cause-and-effect relationship between two variables solely on the basis of an observed association or correlation between them. The idea that "correlation implies causation" is an example of a questionable-cause logical fallacy, in which two events occurring together are taken to have established a cause-and-effect relationship. This fallacy is also known by the Latin phrase cum hoc ergo propter hoc ('with this, therefore because of this'). This differs from the fallacy known as post hoc ergo propter hoc ("after this, therefore because of this"), in which an event following another is seen as a necessary consequence of the former event.

As with any logical fallacy, identifying that the reasoning behind an argument is flawed does not necessarily imply that the resulting conclusion is false. Methods have been proposed that use correlation as the basis for hypothesis tests for causality, including the Granger causality test and convergent cross mapping.

Usage

In logic, the technical use of the word "implies" means "is a Sufficient condition for". This is the meaning intended by statisticians when they say causation is not certain. Indeed, p implies q has the technical meaning of the material conditional: if p then q symbolized as p → q. That is "if circumstance p is true, then q follows." In this sense, it is always correct to say "Correlation does not imply causation." In casual use, the word "implies" loosely means suggests rather than requires.

Where there is causation, there is correlation, but also a sequence in time from cause to effect, a plausible mechanism, and sometimes common and intermediate causes. While correlation is often used when inferring causation because it is a necessary condition, it is not a sufficient condition.

In a widely studied example of the difficulties this possibility of this statistical fallacy poses in deciding cause, numerous epidemiological studies showed that women taking combined hormone replacement therapy (HRT) also had a lower-than-average incidence of coronary heart disease (CHD), leading doctors to propose that HRT was protective against CHD. But later randomized controlled trials showed that use of HRT led to a small but statistically significant increase in the risk of CHD. Reanalysis of the data from the epidemiological studies showed that women undertaking HRT were more likely to be from higher socioeconomic groups (ABC1), with better-than-average diet and exercise regimens. Thus the use of HRT and decreased incidence of coronary heart disease were coincident effects of a common cause (i.e., the benefits associated with a higher socioeconomic status), rather than one being a direct cause of the other, as had been supposed. The widely held (but mistaken) belief that RCTs provide stronger causal evidence than observational studies, the latter continued to consistently show benefits and subsequent analyses and follow-up studies have demonstrated a significant benefit for CHD risk in healthy women initiating oestrogen therapy soon after the onset of menopause.

Causal analysis

Causal analysis is the field of experimental design and statistics pertaining to establishing cause and effect. For any two correlated events, A and B, their possible relationships include:

• A causes B (direct causation);
• B causes A (reverse causation);
• A and B are both caused by C
• A causes B and B causes A (bidirectional or cyclic causation);
• There is no connection between A and B; the correlation is a coincidence.

Thus there can be no conclusion made regarding the existence or the direction of a cause-and-effect relationship only from the fact that A and B are correlated. Determining whether there is an actual cause-and-effect relationship requires further investigation, even when the relationship between A and B is statistically significant, a large effect size is observed, or a large part of the variance is explained.

In philosophy and physics

The nature of causality is systematically investigated in several academic disciplines, including philosophy and physics.

In academia, there are a significant number of theories on causality; The Oxford Handbook of Causation (Beebee, Hitchcock & Menzies 2009) encompasses 770 pages. Among the more influential theories within philosophy are Aristotle's Four causes and Al-Ghazali's occasionalism. David Hume argued that beliefs about causality are based on experience, and experience similarly based on the assumption that the future models the past, which in turn can only be based on experience – leading to circular logic. In conclusion, he asserted that causality is not based on actual reasoning: only correlation can actually be perceived. Immanuel Kant, according to Beebee, Hitchcock & Menzies (2009), held that "a causal principle according to which every event has a cause, or follows according to a causal law, cannot be established through induction as a purely empirical claim, since it would then lack strict universality, or necessity".

Outside the field of philosophy, theories of causation can be identified in classical mechanics, statistical mechanics, quantum mechanics, spacetime theories, biology, social sciences, and law. To establish a correlation as causal within physics, it is normally understood that the cause and the effect must connect through a local mechanism (cf. for instance the concept of impact) or a nonlocal mechanism (cf. the concept of field), in accordance with known laws of nature.

From the point of view of thermodynamics, universal properties of causes as compared to effects have been identified through the Second law of thermodynamics, confirming the ancient, medieval and Cartesian view that "the cause is greater than the effect" for the particular case of thermodynamic free energy. This, in turn, is challenged by popular interpretations of the concepts of nonlinear systems and the butterfly effect, in which small events cause large effects due to, respectively, unpredictability and an unlikely triggering of large amounts of potential energy.

Causality construed from counterfactual states

Intuitively, causation seems to require not just a correlation, but a counterfactual dependence. Suppose that a student performed poorly on a test and guesses that the cause was his not studying. To prove this, one thinks of the counterfactual – the same student writing the same test under the same circumstances but having studied the night before. If one could rewind history, and change only one small thing (making the student study for the exam), then causation could be observed (by comparing version 1 to version 2). Because one cannot rewind history and replay events after making small controlled changes, causation can only be inferred, never exactly known. This is referred to as the Fundamental Problem of Causal Inference – it is impossible to directly observe causal effects.

A major goal of scientific experiments and statistical methods is to approximate as best possible the counterfactual state of the world. For example, one could run an experiment on identical twins who were known to consistently get the same grades on their tests. One twin is sent to study for six hours while the other is sent to the amusement park. If their test scores suddenly diverged by a large degree, this would be strong evidence that studying (or going to the amusement park) had a causal effect on test scores. In this case, correlation between studying and test scores would almost certainly imply causation.

Well-designed experimental studies replace equality of individuals as in the previous example by equality of groups. The objective is to construct two groups that are similar except for the treatment that the groups receive. This is achieved by selecting subjects from a single population and randomly assigning them to two or more groups. The likelihood of the groups behaving similarly to one another (on average) rises with the number of subjects in each group. If the groups are essentially equivalent except for the treatment they receive, and a difference in the outcome for the groups is observed, then this constitutes evidence that the treatment is responsible for the outcome, or in other words the treatment causes the observed effect. However, an observed effect could also be caused "by chance", for example as a result of random perturbations in the population. Statistical tests exist to quantify the likelihood of erroneously concluding that an observed difference exists when in fact it does not (for example see P-value).

Causality predicted by an extrapolation of trends

When experimental studies are impossible and only pre-existing data are available, as is usually the case for example in economics, regression analysis can be used. Factors other than the potential causative variable of interest are controlled for by including them as regressors in addition to the regressor representing the variable of interest. False inferences of causation due to reverse causation (or wrong estimates of the magnitude of causation due to the presence of bidirectional causation) can be avoided by using explanators (regressors) that are necessarily exogenous, such as physical explanators like rainfall amount (as a determinant of, say, futures prices), lagged variables whose values were determined before the dependent variable's value was determined, instrumental variables for the explanators (chosen based on their known exogeneity), etc. See Causality#Statistics and economics. Spurious correlation due to mutual influence from a third, common, causative variable, is harder to avoid: the model must be specified such that there is a theoretical reason to believe that no such underlying causative variable has been omitted from the model.

Examples of illogically inferring causation from correlation

B causes A (reverse causation or reverse causality)

Reverse causation or reverse causality or wrong direction is an informal fallacy of questionable cause where cause and effect are reversed. The cause is said to be the effect and vice versa.

Example 1

The faster that windmills are observed to rotate, the more wind is observed.

Therefore, wind is caused by the rotation of windmills. (Or, simply put: windmills, as their name indicates, are machines used to produce wind.)

In this example, the correlation (simultaneity) between windmill activity and wind velocity does not imply that wind is caused by windmills. It is rather the other way around, as suggested by the fact that wind doesn't need windmills to exist, while windmills need wind to rotate. Wind can be observed in places where there are no windmills or non-rotating windmills—and there are good reasons to believe that wind existed before the invention of windmills.

Example 2

In other cases it may simply be unclear which is the cause and which is the effect. For example:

Children that watch a lot of TV are the most violent. Clearly, TV makes children more violent.

This could easily be the other way round; that is, violent children like watching more TV than less violent ones.

Example 3

A correlation between recreational drug use and psychiatric disorders might be either way around: perhaps the drugs cause the disorders, or perhaps people use drugs to self medicate for preexisting conditions. Gateway drug theory may argue that marijuana usage leads to usage of harder drugs, but hard drug usage may lead to marijuana usage (see also confusion of the inverse). Indeed, in the social sciences where controlled experiments often cannot be used to discern the direction of causation, this fallacy can fuel long-standing scientific arguments. One such example can be found in education economics, between the screening/signaling and human capital models: it could either be that having innate ability enables one to complete an education, or that completing an education builds one's ability.

Example 4

A historical example of this is that Europeans in the Middle Ages believed that lice were beneficial to your health, since there would rarely be any lice on sick people. The reasoning was that the people got sick because the lice left. The real reason however is that lice are extremely sensitive to body temperature. A small increase of body temperature, such as in a fever, will make the lice look for another host. The medical thermometer had not yet been invented, so this increase in temperature was rarely noticed. Noticeable symptoms came later, giving the impression that the lice left before the person got sick.

In other cases, two phenomena can each be a partial cause of the other; consider poverty and lack of education, or procrastination and poor self-esteem. One making an argument based on these two phenomena must however be careful to avoid the fallacy of circular cause and consequence. Poverty is a cause of lack of education, but it is not the sole cause, and vice versa.

Third factor C (the common-causal variable) causes both A and B

The third-cause fallacy (also known as ignoring a common cause or questionable cause) is a logical fallacy where a spurious relationship is confused for causation. It asserts that X causes Y when, in reality, X and Y are both caused by Z. It is a variation on the post hoc ergo propter hoc fallacy and a member of the questionable cause group of fallacies.

All of these examples deal with a lurking variable, which is simply a hidden third variable that affects both causes of the correlation. A difficulty often also arises where the third factor, though fundamentally different from A and B, is so closely related to A and/or B as to be confused with them or very difficult to scientifically disentangle from them (see Example 4).

Example 1

Sleeping with one's shoes on is strongly correlated with waking up with a headache.

Therefore, sleeping with one's shoes on causes headache.

The above example commits the correlation-implies-causation fallacy, as it prematurely concludes that sleeping with one's shoes on causes headache. A more plausible explanation is that both are caused by a third factor, in this case going to bed drunk, which thereby gives rise to a correlation. So the conclusion is false.

Example 2

Young children who sleep with the light on are much more likely to develop myopia in later life.

Therefore, sleeping with the light on causes myopia.

This is a scientific example that resulted from a study at the University of Pennsylvania Medical Center. Published in the May 13, 1999 issue of Nature, the study received much coverage at the time in the popular press. However, a later study at Ohio State University did not find that infants sleeping with the light on caused the development of myopia. It did find a strong link between parental myopia and the development of child myopia, also noting that myopic parents were more likely to leave a light on in their children's bedroom. In this case, the cause of both conditions is parental myopia, and the above-stated conclusion is false.

Example 3

As ice cream sales increase, the rate of drowning deaths increases sharply.

Therefore, ice cream consumption causes drowning.

This example fails to recognize the importance of time of year and temperature to ice cream sales. Ice cream is sold during the hot summer months at a much greater rate than during colder times, and it is during these hot summer months that people are more likely to engage in activities involving water, such as swimming. The increased drowning deaths are simply caused by more exposure to water-based activities, not ice cream. The stated conclusion is false.

Example 4

A hypothetical study shows a relationship between test anxiety scores and shyness scores, with a statistical r value (strength of correlation) of +.59.

Therefore, it may be simply concluded that shyness, in some part, causally influences test anxiety.

However, as encountered in many psychological studies, another variable, a "self-consciousness score", is discovered that has a sharper correlation (+.73) with shyness. This suggests a possible "third variable" problem, however, when three such closely related measures are found, it further suggests that each may have bidirectional tendencies (see "bidirectional variable", above), being a cluster of correlated values each influencing one another to some extent. Therefore, the simple conclusion above may be false.

Example 5

Since the 1950s, both the atmospheric CO₂ level and obesity levels have increased sharply.

Hence, atmospheric CO₂ causes obesity.

Richer populations tend to eat more food and produce more CO₂.

Example 6

HDL ("good") cholesterol is negatively correlated with incidence of heart attack.

Therefore, taking medication to raise HDL decreases the chance of having a heart attack.

Further research has called this conclusion into question. Instead, it may be that other underlying factors, like genes, diet and exercise, affect both HDL levels and the likelihood of having a heart attack; it is possible that medicines may affect the directly measurable factor, HDL levels, without affecting the chance of heart attack.

Bidirectional causation: A causes B, and B causes A

Causality is not necessarily one-way; in a predator-prey relationship, predator numbers affect prey numbers, but prey numbers, i.e. food supply, also affect predator numbers. Another well-known example is that cyclists have a lower Body Mass Index than people who do not cycle. This is often explained by assuming that cycling increases physical activity levels and therefore decreases BMI. Because results from prospective studies on people who increase their bicycle use show a smaller effect on BMI than cross-sectional studies, there may be some reverse causality as well (i.e. people with a lower BMI are more likely to cycle). 

The relationship between A and B is coincidental

The two variables aren't related at all, but correlate by chance. The more things are examined, the more likely it is that two unrelated variables will appear to be related. For example:

• The result of the last home game by the Washington Redskins prior to the presidential election predicted the outcome of every presidential election from 1936 to 2000 inclusive, despite the fact that the outcomes of football games had nothing to do with the outcome of the popular election. This streak was finally broken in 2004 (or 2012 using an alternative formulation of the original rule).
• The Mierscheid law, which correlates the Social Democratic Party of Germany's share of the popular vote with the size of crude steel production in Western Germany.
• Alternating bald–hairy Russian leaders: A bald (or obviously balding) state leader of Russia has succeeded a non-bald ("hairy") one, and vice versa, for nearly 200 years.
• The Bible code, Hebrew words predicting historical events supposedly hidden within the Torah: the huge number of combinations of letters makes appearances of any word in sufficiently lengthy text statistically insignificant.

Use of correlation as scientific evidence

Much of scientific evidence is based upon a correlation of variables – they are observed to occur together. Scientists are careful to point out that correlation does not necessarily mean causation. The assumption that A causes B simply because A correlates with B is often not accepted as a legitimate form of argument.

However, sometimes people commit the opposite fallacy – dismissing correlation entirely. This would dismiss a large swath of important scientific evidence. Since it may be difficult or ethically impossible to run controlled double-blind studies, correlational evidence from several different angles may be useful for prediction despite failing to provide evidence for causation. For example, social workers might be interested in knowing how child abuse relates to academic performance. Although it would be unethical to perform an experiment in which children are randomly assigned to receive or not receive abuse, researchers can look at existing groups using a non-experimental correlational design. If in fact a negative correlation exists between abuse and academic performance, researchers could potentially use this knowledge of a statistical correlation to make predictions about children outside the study who experience abuse, even though the study failed to provide causal evidence that abuse decreases academic performance. The combination of limited available methodologies with the dismissing correlation fallacy has on occasion been used to counter a scientific finding. For example, the tobacco industry has historically relied on a dismissal of correlational evidence to reject a link between tobacco and lung cancer, as did biologist and statistician Ronald Fisher.

Correlation is a valuable type of scientific evidence in fields such as medicine, psychology, and sociology. But first correlations must be confirmed as real, and then every possible causative relationship must be systematically explored. In the end correlation alone cannot be used as evidence for a cause-and-effect relationship between a treatment and benefit, a risk factor and a disease, or a social or economic factor and various outcomes. It is one of the most abused types of evidence, because it is easy and even tempting to come to premature conclusions based upon the preliminary appearance of a correlation.

Freakonomics

From Wikipedia, the free encyclopedia

Freakonomics:
A Rogue Economist Explores
the Hidden Side of Everything

Hardcover edition
Author	Steven D. Levitt Stephen J. Dubner
Country	United States
Language	English
Subject	Economics, Sociology
Genre	Non-fiction
Publisher	William Morrow
Publication date	April 12, 2005
Media type	Hardback & Paperback
Pages	336 pp (hardback edition)
ISBN	0-06-123400-1 (Hardback), ISBN 0-06-089637-X (large print paperback)
OCLC	73307236
Followed by	SuperFreakonomics

Freakonomics: A Rogue Economist Explores the Hidden Side of Everything is the debut non-fiction book by University of Chicago economist Steven Levitt and New York Times journalist Stephen J. Dubner. Published on April 12, 2005, by William Morrow, the book has been described as melding pop culture with economics. By late 2009, the book had sold over 4 million copies worldwide.

Overview

The book is a collection of articles written by Levitt, an expert who had gained a reputation for applying economic theory to diverse subjects not usually covered by "traditional" economists. In Freakonomics, Levitt and Dubner argue that economics is, at root, the study of incentives. The book's chapters cover:

• Chapter 1: Discovering cheating as applied to teachers and sumo wrestlers, as well as a typical Washington, D.C.–area bagel business and its customers
• Chapter 2: Information control as applied to the Ku Klux Klan and real-estate agents
• Chapter 3: The economics of drug dealing, including the surprisingly low earnings and abject working conditions of crack cocaine dealers
• Chapter 4: The role legalized abortion has played in reducing crime, contrasted with the policies and downfall of Romanian dictator Nicolae Ceauşescu (Levitt explored this topic in an earlier paper entitled "The Impact of Legalized Abortion on Crime," written with John Donohue.)
• Chapter 5: The negligible effects of good parenting on education
• Chapter 6: The socioeconomic patterns of naming children (nominative determinism)

One example of the authors' use of economic theory involves demonstrating the existence of cheating among sumo wrestlers. In a sumo tournament, all wrestlers in the top division compete in 15 matches and face demotion if they do not win at least eight of them. The sumo community is very close-knit, and the wrestlers at the top levels tend to know each other well. The authors looked at the final match, and considered the case of a wrestler with seven wins, seven losses, and one fight to go, fighting against an 8–6 wrestler. Statistically, the 7–7 wrestler should have a slightly below even chance, since the 8–6 wrestler is slightly better. However, the 7–7 wrestler actually wins around 80% of the time. Levitt uses this statistic and other data gleaned from sumo wrestling matches, along with the effect that allegations of corruption have on match results, to conclude that those who already have 8 wins collude with those who are 7–7 and let them win, since they have already secured their position for the following tournament. Despite condemnation of the claims by the Japan Sumo Association following the book's publication in 2005, the 2011 Grand Tournament in Tokyo was canceled for the first time since 1946 because of allegations of match-fixing.

The authors attempt to demonstrate the power of data mining, as a number of their results emerge from Levitt's analysis of various databases. The authors posit that various incentives encourage teachers to cheat by assisting their students with multiple-choice high-stakes tests. Such cheating in the Chicago school system is inferred from detailed analysis of students' answers to multiple-choice questions. Levitt asks, "What would the pattern of answers look like if the teacher cheated?", and hypothesizes that the more difficult questions found at the end of test sections will be answered correctly more frequently than the easy questions at the beginning of test sections.

Second edition

In Chapter 2 of Freakonomics, the authors wrote of their visit to folklorist Stetson Kennedy's Florida home where the topic of Kennedy's investigations of the Ku Klux Klan were discussed. However, in their January 8, 2006, column in The New York Times Magazine, Dubner and Levitt wrote of questions about Stetson Kennedy's research ("Hoodwinked", pp. 26–28) leading to the conclusion that Kennedy's research was at times embellished for effectiveness.

In the "Revised and Expanded Edition" this embellishment was noted and corrected: "Several months after Freakonomics was first published, it was brought to our attention that this man's portrayal of his crusade, and various other Klan matters, was considerably overstated ... we felt it was important to set straight the historical record."

Criticism

Freakonomics has been criticized for being a work of sociology or criminology, rather than economics. Israeli economist Ariel Rubinstein criticized the book for making use of dubious statistics and complained that "economists like Levitt ... have swaggered off into other fields", saying that the "connection to economics ... [is] none" and that the book is an example of "academic imperialism". Arnold Kling has suggested the book is an example of "amateur sociology".

The impact of legalized abortion on crime

Revisiting a question first studied empirically in the 1960s, Donohue and Levitt argue that the legalization of abortion can account for almost half of the reduction in crime witnessed in the 1990s. This paper has sparked much controversy, to which Levitt has said

"The numbers we're talking about, in terms of crime, are absolutely trivial when you compare it to the broader debate on abortion. From a pro-life view of the world: If abortion is murder then we have a million murders a year through abortion. And the few thousand homicides that will be prevented according to our analysis are just nothing—they are a pebble in the ocean relative to the tragedy that is abortion. So, my own view, when we [did] the study and it hasn't changed is that: our study shouldn't change anybody's opinion about whether abortion should be legal and easily available or not. It's really a study about crime, not abortion."

In 2003, Theodore Joyce argued that legalized abortion had little impact on crime, contradicting Donohue and Levitt's results ("Did Legalized Abortion Lower Crime?" Journal of Human Resources, 2003, 38(1), pp. 1–37). In 2004, the authors published a response, in which they argued that Joyce's argument was flawed due to omitted-variable bias.

In November 2005, Federal Reserve Bank of Boston economist Christopher Foote and his research assistant Christopher Goetz published a working paper, in which they argued that the results in Donohue and Levitt's abortion and crime paper were due to statistical errors made by the authors: the omission of state-year interactions and the use of the total number of arrests instead of the arrest rate in explaining changes in the murder rate. When the corrections were made, Foote and Goetz argued that abortion actually increased violent crime instead of decreasing it and did not affect property crime. They even concluded that the majority of women who had abortions in the 1970s were middle class whites rather than low income minorities as Levitt stated; this was, they stated, because white middle-class women had the financial means for an abortion. The Economist remarked on the news of the errors that "for someone of Mr Levitt's iconoclasm and ingenuity, technical ineptitude is a much graver charge than moral turpitude. To be politically incorrect is one thing; to be simply incorrect quite another." In January 2006, Donohue and Levitt published a response, in which they admitted the errors in their original paper but also pointed out Foote and Goetz's correction was flawed due to heavy attenuation bias. The authors argued that, after making necessary changes to fix the original errors, the corrected link between abortion and crime was now weaker but still statistically significant, contrary to Foote and Goetz's claims. Foote and Goetz, however, soon produced a rebuttal of their own and said that even after analyzing the data using the methods that Levitt and Donohue recommend, the data does not show a positive correlation between abortion rates and crime rates. They are quick to point out that this does not necessarily disprove Levitt's thesis, however, and emphasize that with data this messy and incomplete, it is in all likelihood not even possible to prove or disprove Donohue and Levitt's conclusion.

Freakonomics commented on the effects of an abortion ban in Romania (Decree 770), stating that "Compared to Romanian children born just a year earlier, the cohort of children born after the abortion ban would do worse in every measurable way: they would test lower in school, they would have less success in the labor market, and they would also prove much more likely to become criminals. (p. 118)". John DiNardo, a professor at the University of Michigan, retorts that the paper cited by Freakonomics states "virtually the opposite of what is actually claimed":

On average, children born in 1967 just after abortions became illegal display better educational and labor market achievements than children born prior to the change. This outcome can be explained by a change in the composition of women having children: urban, educated women were more likely to have abortions prior to the policy change, so a higher proportion of children were born into urban, educated households. (Pop-Eleches, 2002, p. 34).

— John DiNardo, Freakonomics: Scholarship in the Service of Storytelling

Levitt responded on the Freakonomics Blog that Freakonomics and Pop-Eleches "are saying the same thing":

Here is the abstract of the version of the Pop-Eleches paper that we cited:

…Children born after the abortion ban attained more years of schooling and greater labor market success. This is because urban, educated women were more likely to have abortions prior to the policy change, and the relative number of children born to this type of woman increased after the ban. However, controlling for composition using observable background variables, children born after the ban on abortions had worse educational and labor market achievements as adults. Additionally, I provide evidence of crowding in the school system and some suggestive evidence that cohorts born after the introduction of the abortion ban had higher infant mortality and increased criminal behavior later in life.

The introduction of the Pop-Eleches paper says:

This finding is consistent with the view that children who were unwanted during pregnancy had worse socio-economic outcomes once they became adults.

Effects of extra police on crime

Freakonomics claimed that it was possible to "tease out" the effect of extra police on crime by analyzing electoral cycles. The evidence behind these claims was shown to be due partly to a programming error. McCrary stated "While municipal police force size does appear to vary over state and local electoral cycles ... elections do not induce enough variation in police hiring to generate informative estimates of the effect of police on crime."

Defamation case

On April 10, 2006, John Lott filed suit for defamation against Steven Levitt and HarperCollins Publishers over the book and against Levitt over a series of emails to retired economist John B. McCall. In the book Freakonomics, Levitt and coauthor Stephen J. Dubner claimed that the results of Lott's research in More Guns, Less Crime had not been replicated by other academics. In the emails to McCall, who had pointed to a number of papers in different academic publications that had replicated Lott's work, Levitt wrote that the work by authors supporting Lott in a special 2001 issue of The Journal of Law and Economics had not been peer-reviewed, alleged that Lott had paid the University of Chicago Press to publish the papers, and that papers with results opposite of Lott's had been blocked from publication in that issue.

A federal judge found that Levitt's replication claim in Freakonomics was not defamation but found merit in Lott's complaint about the email claims.

Levitt settled the second defamation claim by admitting in a letter to John B. McCall that he himself was a peer reviewer in the 2001 issue of The Journal of Law and Economics, that Lott had not engaged in bribery (paying for extra costs of printing and postage for a conference issue is customary), and that he knew that "scholars with varying opinions" (including Levitt himself) had been invited to participate. The Chronicle of Higher Education characterized Levitt's letter as offering "a doozy of a concession".

The dismissal of the first half of Lott's suit was unanimously upheld by the United States Court of Appeals for the Seventh Circuit on February 11, 2009.

Publishing history

Freakonomics peaked at number two among nonfiction on The New York Times Best Seller list and was named the 2006 Book Sense Book of the Year in the Adult Nonfiction category. The book received positive reviews from critics. The review aggregator Metacritic reported the book had an average score of 67 out of 100, based on 16 reviews. Freakonomics has a social review score 69/100 on Panjury.

Screen shot of Freakonomics Blog

The success of the book has been partly attributed to the blogosphere. In the campaign prior to the release of the book in April 2005, publisher (William Morrow and Company) chose to target bloggers in an unusually strategic way, sending galley copies to over a hundred of them, as well as contracting two specialized buzz marketing agencies.

In 2006, the Revised and Expanded Edition of the book was published, with the most significant corrections in the second chapter.

Progression

Freakonomics blog

The authors started their own Freakonomics blog in 2005.

In May 2007, writer and blogger Melissa Lafsky was hired as the full-time editor of the site. In August 2007, the blog was incorporated into The New York Times' web site – the authors had been writing joint columns for The New York Times Magazine since 2004 – and the domain Freakonomics.com became a redirect there. In March 2008, Annika Mengisen replaced Lafsky as the blog editor. The Freakonomics blog ended its association with The New York Times on March 1, 2011.

Among the recurrent guest bloggers on the Freakonomics blog are Ian Ayres, Daniel Hamermesh, Eric A. Morris, Sudhir Venkatesh, Justin Wolfers and others.

In 2008, Stephen Dubner asked for questions from the site's readers and then featured them in an extended Q&A on "Best Places to Live" with demographics expert Bert Sperling.

SuperFreakonomics

Main article: SuperFreakonomics

In April 2007, co-author Stephen Dubner announced that there would be a sequel to Freakonomics, and that it would contain further writings about street gang culture from Sudhir Venkatesh, as well as a study of the use of money by capuchin monkeys. Dubner said the title would be SuperFreakonomics, and that one topic would be what makes people good at what they do. The book was released in Europe in early October 2009 and in the United States on October 20, 2009.

Freakonomics radio

In September 2010, Marketplace radio announced the creation of a Freakonomics podcast hosted by Dubner and Levitt. It is available on iTunes and is aired bi-weekly on NPR.

Film adaptation

In 2010, Chad Troutwine, Chris Romano, and Dan O'Meara produced a documentary film adaptation with a budget of nearly US$3 million in an omnibus format by directors Seth Gordon, Morgan Spurlock, Alex Gibney, Eugene Jarecki, Rachel Grady, and Heidi Ewing. It was the Closing Night Gala premiere film at the Tribeca Film Festival on April 30, 2010. It was also the Opening Night film at the AFI/Discovery SilverDocs film festival on June 21, 2010. Magnolia Pictures acquired distribution rights for a Fall 2010 release.

Freakonomics: The Movie was released in major cities with a pay what you want pricing offer for selected preview showings. No report of the results has yet been published.

Freakonomics Consulting Group

In 2009, Steven Levitt co-founded Freakonomics Consulting Group, a business and philanthropy consulting company which became The Greatest Good and is now known as TGG Group. Founding partners include Nobel laureates Daniel Kahneman and Gary Becker, as well as several other prominent economists.

 

Plea bargain

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Mandatory_sentencing 

A plea bargain (also plea agreement or plea deal) is any agreement in a criminal case between the prosecutor and defendant whereby the defendant agrees to plead guilty or nolo contendere to a particular charge in return for some concession from the prosecutor. This may mean that the defendant will plead guilty to a less serious charge, or to one of the several charges, in return for the dismissal of other charges; or it may mean that the defendant will plead guilty to the original criminal charge in return for a more lenient sentence.

A plea bargain allows both parties to avoid a lengthy criminal trial and may allow criminal defendants to avoid the risk of conviction at trial on a more serious charge. For example, in the legal system of the United States, a criminal defendant charged with a felony theft charge, the conviction of which would require imprisonment in state prison, may be offered the opportunity to plead guilty to a misdemeanor theft charge, which may not carry a custodial sentence.

In cases such as an automobile collision when there is a potential for civil liability against the defendant, the defendant may agree to plead "no contest" or "guilty with a civil reservation", which essentially is a guilty plea without admitting civil liability.

Plea bargaining can present a dilemma to defense attorneys, in that they must choose between vigorously seeking a good deal for their present client, or maintaining a good relationship with the prosecutor for the sake of helping future clients. However, in the case of the USA for example, defense attorneys are required by the ethics of the bar to defend the present client's interests over the interests of others. Violation of this rule may result in disciplinary sanctions being imposed against the defense attorney by the appropriate state's bar association.

In charge bargaining, defendants plead guilty to a less serious crime than the original charge that was filed against them. In count bargaining, they plead guilty to a subset of multiple original charges. In sentence bargaining, they plead guilty agreeing in advance what sentence will be given; however, this sentence can still be denied by the judge. In fact bargaining, defendants plead guilty but the prosecutor agrees to stipulate (i.e., to affirm or concede) certain facts that will affect how the defendant is punished under the sentencing guidelines.

Plea bargaining was considered a predominantly US-American phenomenon during the 1970s, but has since spread throughout the world.

Advantages

Plea bargaining has been defended as a voluntary exchange that leaves both parties better off, in that defendants have many procedural and substantive rights, including a right to trial and to appeal a guilty verdict. By pleading guilty, defendants waive those rights in exchange for a commitment from the prosecutor, such as a reduced charge or more favorable sentence. For a defendant who believes that conviction is almost certain, a discount to the sentence is more useful than an unlikely chance of acquittal. The prosecutor secures a conviction while avoiding the need to commit time and resources to trial preparation and a possible trial. Plea bargaining similarly helps preserve money and resources for the court in which the prosecution occurs. It also means that victims and witnesses do not have to testify at the trial, which in some cases may be traumatic.

Disadvantages and issues

Scope for coercive manipulation

Plea bargaining is criticized, particularly outside the United States, on the grounds that its close relationship with rewards, threats and coercion potentially endanger the correct legal outcome.

Author Martin Yant discusses the use of coercion in plea bargaining:

Even when the charges are more serious, prosecutors often can still bluff defense attorneys and their clients into pleading guilty to a lesser offense. As a result, people who might have been acquitted because of lack of evidence, but also who are in fact truly innocent, will often plead guilty to the charge. Why? In a word, fear. And the more numerous and serious the charges, studies have shown, the greater the fear. That explains why prosecutors sometimes seem to file every charge imaginable against defendants.

This tactic is prohibited in some other countries—for example in the United Kingdom the prosecutor's code states:

Prosecutors should never go ahead with more charges than are necessary just to encourage a defendant to plead guilty to a few. In the same way, they should never go ahead with a more serious charge just to encourage a defendant to plead guilty to a less serious one.

although it adds that in some kinds of complex cases such as major fraud trials:

The over-riding duty of the prosecutor is ... to see that justice is done. The procedures must command public and judicial confidence. Many defendants in serious and complex fraud cases are represented by solicitors experienced in commercial litigation, including negotiation. This means that the defendant is usually protected from being put under improper pressure to plead. The main danger to be guarded against in these cases is that the prosecutor is persuaded to agree to a plea or a basis that is not in the public interest and interests of justice because it does not adequately reflect the seriousness of the offending ... Any plea agreement must reflect the seriousness and extent of the offending and give the court adequate sentencing powers. It must consider the impact of an agreement on victims and also the wider public, whilst respecting the rights of defendants.

John H. Langbein argues that the modern American system of plea bargaining is comparable to the medieval European system of torture:

There is, of course, a difference between having your limbs crushed if you refuse to confess, or suffering some extra years of imprisonment if you refuse to confess, but the difference is of degree, not kind. Plea bargaining, like torture, is coercive. Like the medieval Europeans, the Americans are now operating a procedural system that engages in condemnation without adjudication.

Consequences for innocent accused

Theoretical work based on the prisoner's dilemma is one reason that, in many countries, plea bargaining is forbidden. Often, precisely the prisoner's dilemma scenario applies: it is in the interest of both suspects to confess and testify against the other suspect, irrespective of the innocence of the accused. Arguably, the worst case is when only one party is guilty: here, the innocent one has no incentive to confess, while the guilty one has a strong incentive to confess and give testimony (including false testimony) against the innocent.

A 2009 study by the European Association of Law and Economics observed that innocent defendants are consistently more likely than guilty defendants to reject otherwise-favorable pleas proposals, even when theoretically disadvantageous to do so, because of perceived unfairness, and would do so even if the expected sanction would be worse if they proceeded to trial. The study concluded that "[t]his somewhat counterintuitive 'cost of innocence', where the preferences of innocents lead them collectively to fare worse than their guilty counterparts, is further increased by the practice of imposing much harsher sentences at trial on defendants who contest the charges. This 'trial penalty' seeks to facilitate guilty pleas by guilty defendants [...and ironically...] disproportionately, collectively, penalizes innocents, who reject on fairness grounds some offers their guilty counterparts accept."

The extent to which innocent people will accept a plea bargain and plead guilty is contentious and has been subjected to considerable research. Much research has focused on the relatively few actual cases where innocence was subsequently proven, such as successful appeals for murder and rape based upon DNA evidence, which tend to be atypical of trials as a whole (being by their nature only the most serious kinds of crime). Other studies have focused on presenting hypothetical situations to subjects and asking what choice they would make. More recently some studies have attempted to examine actual reactions of innocent persons generally, when faced with actual plea bargain decisions. A study by Dervan and Edkins (2013) attempted to recreate a real-life controlled plea bargain situation, rather than merely asking theoretical responses to a theoretical situation—a common approach in previous research. It placed subjects in a situation where an accusation of academic fraud (cheating) could be made, of which some subjects were in fact by design actually guilty (and knew this), and some were innocent but faced seemingly strong evidence of guilt and no verifiable proof of innocence. Each subject was presented with the evidence of guilt and offered a choice between facing an academic ethics board and potentially a heavy penalty in terms of extra courses and other forfeits, or admitting guilt and accepting a lighter "sentence". The study found that as expected from court statistics, around 90% of accused subjects who were actually guilty chose to take the plea-bargain and plead guilty. It also found that around 56% of subjects who were actually innocent (and privately knew it) also to take the plea-bargain and plead guilty, for reasons including avoiding formal quasi-legal processes, uncertainty, possibility of greater harm to personal future plans, or deprivation of home environment due to remedial courses. The authors stated:

Previous research has argued that the innocence problem is minimal because defendants are risk-prone and willing to defend themselves before a tribunal. Our research, however, demonstrates that when study participants are placed in real, rather than hypothetical, bargaining situations and are presented with accurate information regarding their statistical probability of success, just as they might be so informed by their attorney or the government during a criminal plea negotiation, innocent defendants are highly risk-averse.

More pressure to plea bargain may be applied in weak cases (where there is less certainty of both guilt and jury conviction) than strong cases. Prosecutors tend to be strongly motivated by conviction rates, and "there are many indications that prosecutors are willing to go a long way to avoid losing cases, [and that] when prosecutors decide to proceed with such weak cases they are often willing to go a long way to assure that a plea bargain is struck". Prosecutors often have great power to procure a desired level of incentive, as they select the charges to be presented. For this reason,

[P]lea bargains are just as likely in strong and weak cases. Prosecutors only need to adjust the offer to the probability of conviction in order to reach an agreement. Thus, weaker cases result in more lenient plea bargains, and stronger ones in relative harshness, but both result in an agreement. [... W]hen the case is weak, the parties must rely on charge bargaining ... But [charge bargaining] is hardly an obstacle. Charge bargaining in weak cases is not the exception; it is the norm all around the country. Thus, even if the evidence against innocent defendants is, on average, weaker, the likelihood of plea bargains is not dependent on guilt.

Another situation in which an innocent defendant may plead guilty is in the case of a defendant who cannot raise bail, and who is being held in custody in a jail or detention facility. Because it may take months, or even years, for criminal cases to come to trial or even indictment in some jurisdictions, an innocent defendant who is offered a plea bargain that includes a sentence of less time than they would otherwise spend in jail awaiting an indictment or a trial may choose to accept the plea arrangement and plead guilty.

Misalignment of goals and incentives

Agency problems may arise in plea bargaining as, although the prosecutor represents the people and the defense attorney represents the defendant, these agents' goals may not be congruent with those of their principals. For example, prosecutors and defense attorneys may seek to maintain good relations with one another, creating a potential conflict with the parties they represent. A defense attorney may receive a flat fee for representing a client, or may not receive additional money for taking a case to trial, creating an incentive for the defense attorney to settle a case to increase profits or to avoid a financial loss.

A prosecutor may want to maintain a high conviction rate or avoid a losing high-profile trials, creating the potential that they will enter into a plea bargain that furthers their interests but reduces the potential of the prosecution and sentence to deter crime. Prosecutors may also make charging decisions that significantly affect a defendant's sentence, and may file charges or offer plea deals that cause even an innocent defendant to consider or accept a plea bargain.

Issues related to cost of justice

Another argument against plea bargaining is that it may not actually reduce the costs of administering justice. For example, if a prosecutor has only a 25% chance of winning his case and sending a defendant away to prison for 10 years, they may make a plea agreement for a sentence of one year; but if plea bargaining is unavailable, a prosecutor may drop the case completely.

Usage in common law countries

United States

Plea bargaining is a significant part of the criminal justice system in the United States; the vast majority (roughly 90%) of criminal cases in the United States are settled by plea bargain rather than by a jury trial. Plea bargains are subject to the approval of the court, and different states and jurisdictions have different rules. The Federal Sentencing Guidelines are followed in federal cases and have been created to ensure a standard of uniformity in all cases decided in the federal courts. A two- or three-level offense level reduction is usually available for those who accept responsibility by not holding the prosecution to the burden of proving its case; this usually amounts to a complete sentence reduction had they gone to trial and lost.

The Federal Rules of Criminal Procedure provide for two main types of plea agreements. An 11(c)(1)(B) agreement does not bind the court; the prosecutor's recommendation is merely advisory, and the defendant cannot withdraw their plea if the court decides to impose a sentence other than what was stipulated in the agreement. An 11(c)(1)(C) agreement, however, binds the court once the court accepts the agreement. When such an agreement is proposed, the court can reject it if it disagrees with the proposed sentence, in which case the defendant has an opportunity to withdraw their plea.

Plea bargains are so common in the Superior Courts of California (the general trial courts) that the Judicial Council of California has published an optional seven-page form (containing all mandatory advisements required by federal and state law) to help prosecutors and defense attorneys reduce such bargains into written plea agreements.

Certain aspects of the American justice system serve to promote plea bargaining. For example, the adversarial nature of the U.S. criminal justice system puts judges in a passive role, in which they have no independent access to information with which to assess the strength of the case against the defendant. The prosecutor and defense may thus control the outcome of a case through plea bargaining. The court must approve a plea bargain as being within the interests of justice.

The lack of compulsory prosecution also gives prosecutors greater discretion as well as the inability of crime victims to mount a private prosecution and their limited ability to influence plea agreements. Defendants who are held in custody—who either do not have the right to bail or cannot afford bail, or who do not qualify for release on their own recognizance—may get out of jail immediately following the judge's acceptance of a plea.

Generally, once a plea bargain is made and accepted by the courts, the matter is final and cannot be appealed. However, a defendant may withdraw his plea for certain legal reasons, and a defendant may agree to a "conditional" plea bargain, whereby they plead guilty and accept a sentence, but reserve the right to appeal a specific matter (such as violation of a constitutional right). If the defendant does not win on appeal the agreement is carried out; if the defendant is successful on appeal the bargain is terminated. The defendant in Doggett v. United States made such a bargain, reserving the right to appeal solely on the grounds that he was not given a speedy trial as required by the United States Constitution; Doggett's claim was upheld by the United States Supreme Court and he was freed.

Canada

In Canada, the courts always have the final say with regard to sentencing. Nevertheless, plea bargaining has become an accepted part of the criminal justice system although judges and Crown attorneys are often reluctant to refer to it as such. In most Canadian criminal proceedings, the Crown has the ability to recommend a lighter sentence than it would seek following a guilty verdict in exchange for a guilty plea.

Like other common law jurisdictions, the Crown can also agree to withdraw some charges against the defendant in exchange for a guilty plea. This has become standard procedure for certain offences such as impaired driving. In the case of hybrid offences, the Crown must make a binding decision as to whether to proceed summarily or by indictment prior to the defendant making his or her plea. If the Crown elects to proceed summarily and the defendant then pleads not guilty, the Crown cannot change its election. Therefore, the Crown is not in a position to offer to proceed summarily in exchange for a guilty plea.

Canadian judges are not bound by the Crown's sentencing recommendations and could impose harsher (or more lenient) penalties. Therefore, the Crown and the defence will often make a joint submission with respect to sentencing. While a joint submission can entail both the Crown and defence recommending exactly the same disposition of a case, this is not common except in cases that are sufficiently minor that the Crown is willing to recommend a discharge. In more serious cases, a joint submission normally call for a sentence within relatively narrow range, with the Crown arguing for a sentence at the upper end of the range and the defence arguing for a sentence at the lower end, so as to maintain the visibility of the judge's ability to exercise discretion.

Judges are not bound to impose a sentence within the range of a joint submission, and a judge's disregard for a joint submission is not in itself grounds for the sentence to be altered on appeal. However, if a judge routinely disregards joint submissions, that judge would compromise the ability of the Crown to offer meaningful incentives for defendants to plead guilty. Defence lawyers would become reluctant to enter into joint submissions if they were thought to be of little value with a particular judge, which would thus result in otherwise avoidable trials. For these reasons, Canadian judges will normally impose a sentence within the range of any joint submission.

Following a Supreme Court of Canada ruling that imposes strict time limits on the resolution of criminal cases (eighteen months for cases in provincial court and thirty months for cases in Superior Court), several provinces have initiated and intensified measures intended to maximize the number of minor criminal cases resolved by a plea bargain.

Largely particular to the Canadian justice system is that further negotiations concerning the final disposition of a criminal case may also arise even after a sentence has been passed. This is because in Canada the Crown has (by common law standards) a very broad right to appeal acquittals, and also a right to appeal for harsher sentences except in cases where the sentence imposed was maximum allowed. Therefore, in Canada, after sentencing the defence sometimes has an incentive to try and persuade the Crown to not appeal a case, in exchange for the defence also declining to appeal. While, strictly speaking, this is not plea bargaining, it is done for largely the same reasons.

England and Wales

Plea bargaining is permitted in the legal system of England and Wales. The guidelines by the Sentencing Council require that the discount it gives to the sentence be determined by the timing of the plea and no other factors. The guidelines state that the earlier the guilty plea is entered, the greater the discount to the sentence. The maximum discount permitted is one third, for a plea entered at the earliest stage. There is no minimum discount; a guilty plea entered on the first proper day of the trial would be expected provide a discount of one tenth. The discount can sometimes involve changing the type of punishment, such as substituting a prison sentence for community service.

Plea bargaining in Magistrates' Court trials is permitted only to the extent that the prosecutors and the defence can agree that the defendant will plead guilty to some charges and the prosecutor will drop the remainder. However, although this is not conducting a plea bargain, in cases before the Crown Court, the defence can request an indication from the judge of the likely maximum sentence that would be imposed should the defendant decide to plead guilty.

In the case of hybrid offences in England and Wales, the decision whether to deal with a case in Magistrates' Court or Crown Court is not made by magistrates until after a plea has been entered. A defendant is thus unable to plead guilty in exchange for having a case dealt with in Magistrates' Court (which has lesser sentencing powers).

India

Plea bargaining was introduced in India by The Criminal Law (Amendment) Act, 2005, which amended the Code of Criminal Procedure and introduced a new chapter, XXI(A), in the code, enforceable from July 5, 2006. It allows plea bargaining for cases in which the maximum punishment is imprisonment for seven years; however, offenses affecting the socio-economic condition of the country and offenses committed against a woman or a child below 14 are excluded.

In 2007, the Sakharam Bandekar case became the first such case in India where the accused, Sakharam Bandekar, requested lesser punishment in return for confessing to his crime (using plea bargaining). However, the court rejected his plea and accepted the CBI's argument that the accused was facing serious charges of corruption. Finally, the court convicted Bandekar and sentenced him to three years' imprisonment.

Pakistan

Plea bargaining as a formal legal provision was introduced in Pakistan by the National Accountability Ordinance 1999, an anti-corruption law. A special feature of this plea bargain is that the accused applies for it, accepting guilt, and offers to return the proceeds of corruption as determined by investigators and prosecutors. After an endorsement by the Chairman National Accountability Bureau, the request is presented before the court, which decides whether it should be accepted or not. If the request for plea bargain is accepted by the court, the accused stands convicted but neither is sentenced if in trial nor undergoes any sentence previously pronounced by a lower court if in appeal. The accused is disqualified to take part in elections, hold any public office, or obtain a loan from any bank; the accused is also dismissed from service if a government official.

In other cases, formal plea bargains in Pakistan are limited, but the prosecutor has the authority to drop a case or a charge in a case and, in practice, often does so, in return for a defendant pleading guilty on some lesser charge. No bargaining takes place over the penalty, which is the court's sole privilege.

Other common law jurisdictions

In some common law jurisdictions, such as Singapore and the Australian state of Victoria, plea bargaining is practiced only to the extent that the prosecution and the defense can agree that the defendant will plead guilty to some charges or to reduced charges in exchange for the prosecutor withdrawing the remaining or more serious charges. In New South Wales, a 10-25% discount on the sentence is customarily given in exchange for an early guilty plea, but this concession is expected to be granted by the judge as a way of recognizing the utilitarian value of an early guilty plea to the justice system - it is never negotiated with a prosecutor. The courts in these jurisdictions have made it plain that they will always decide what the appropriate penalty is to be. No bargaining takes place between the prosecution and the defence over criminal penalties.

Use in civil law countries

Plea bargaining is extremely difficult in jurisdictions based on the civil law. This is because, unlike common law systems, civil law systems have no concept of plea—if the defendant confesses; a confession is entered into evidence, but the prosecution is not absolved of the duty to present a full case. A court may decide that a defendant is innocent even though they presented a full confession. Also, unlike common law systems, prosecutors in civil law countries may have limited or no power to drop or reduce charges after a case has been filed, and in some countries their power to drop or reduce charges before a case has been filed is limited, making plea bargaining impossible. Since the 1980s, many civil law nations have adapted their systems to allow for plea bargaining.

Brazil

In 2013 Brazil passed a law allowing plea bargains, which have been used in the political corruption trials taking place since then.

Central African Republic

In the Central African Republic, witchcraft carries heavy penalties but those accused of it typically confess in exchange for a modest sentence.

China

In China, a plea bargaining pilot scheme was introduced by the Standing Committee of the National People's Congress in 2016. For defendants that face jail terms of three years or fewer, agrees to plead guilty voluntarily and agree with prosecutors' crime and sentencing proposals are given mitigated punishments.

Denmark

In 2009, in a case about whether witness testimony originating from a plea deal in the United States was admissible in a Danish criminal trial (297/2008 H), the Supreme Court of Denmark (Danish: Højesteret) unanimously ruled that plea bargains are prima facie not legal under Danish law, but that the witnesses in the particular case would be allowed to testify regardless (with the caveat that the lower court consider the possibility that the testimony was untrue or at least influenced by the benefits of the plea bargain). The Supreme Court did, however, point out that Danish law contains mechanisms similar to plea bargains, such as § 82, nr. 10 of the Danish Penal Code (Danish: Straffeloven) which states that a sentence may be reduced if the perpetrator of a crime provides information that helps solve a crime perpetrated by others, or § 23 a of the Danish Competition Law (Danish: Konkurrenceloven) which states that someone can apply to avoid being fined or prosecuted for participating in a cartel if they provide information about the cartel that the authorities did not know at the time.

If a defendant admits to having committed a crime, the prosecution does not have to file charges against them, and the case can be heard as a so-called "admission case" (Danish: tilståelsessag) under § 831 of the Law on the Administration of Justice (Danish: Retsplejeloven) provided that: the confession is supported by other pieces of evidence (meaning that a confession is not enough to convict someone on its own); both the defendant and the prosecutor consent to it; the court does not have any objections; §§ 68, 69, 70 and 73 of the penal code do not apply to the case.

Estonia

In Estonia, plea bargaining was introduced in the 1990s: the penalty is reduced in exchange for confession and avoiding most of the court proceedings. Plea bargaining is permitted for the crimes punishable by no more than four years of imprisonment. Normally, a 25% reduction of the penalty is given.

France

The introduction of a limited form of plea bargaining (comparution sur reconnaissance préalable de culpabilité or CRPC, often summarized as plaider coupable) in 2004 was highly controversial in France. In this system, the public prosecutor could propose to suspects of relatively minor crimes a penalty not exceeding one year in prison; the deal, if accepted, had to be accepted by a judge. Opponents, usually lawyers and leftist political parties, argued that plea bargaining would greatly infringe on the rights of defense, the long-standing constitutional right of presumption of innocence, the rights of suspects in police custody, and the right to a fair trial.

For instance, Robert Badinter argued that plea bargaining would give too much power to the public prosecutor and would encourage defendants to accept a sentence only to avoid the risk of a bigger sentence in a trial, even if they did not really deserve it. Only a minority of criminal cases are settled by that method: in 2009, 77,500 out of the 673,700 or 11.5% of the decisions by the correctional courts.

Georgia

Plea bargaining (Georgian: საპროცესო შეთანხმება, literally "plea agreement") was introduced in Georgia in 2004. The substance of the Georgian plea bargaining is similar to the United States and other common law jurisdictions.

A plea bargaining, also called a plea agreement or negotiated plea, is an alternative and consensual way of criminal case settlement. A plea agreement means settlement of case without main hearing when the defendant agrees to plead guilty in exchange for a lesser charge or for a more lenient sentence or for dismissal of certain related charges. (Article 209 of the Criminal Procedure Code of Georgia)

Defendants' rights during plea bargaining

The main principle of the plea bargaining is that it must be based on the free will of the defendant, equality of the parties and advanced protection of the rights of the defendant:

• In order to avoid fraud of the defendant or insufficient consideration of his or her interests, legislation foresees obligatory participation of the defense council; (Article 210 of the Criminal Procedure Code of Georgia)
  
• The defendant has the right to reject the plea agreement on any stage of the criminal proceedings before the court renders the judgment. (Article 213 of the Criminal Procedure Code of Georgia)
  
• In case of refusal, it is prohibited to use information provided by the defendant under the plea agreement against him or her in the future. (Article 214 of the Criminal Procedure Code of Georgia)
  
• The defendant has the right to appeal the judgment rendered consequent to the plea agreement if the plea agreement was concluded by deception, coercion, violence, threat, or violence. (Article 215 of the Criminal Procedure Code of Georgia)

Obligations of the prosecutor while concluding the plea agreement

While concluding the plea agreement, the prosecutor is obliged to take into consideration public interest, severity of the penalty, and personal characteristics of the defendant. (Article 210 of the Criminal Procedure Code of Georgia) To avoid abuse of powers, legislation foresees written consent of the supervisory prosecutor as necessary precondition to conclude plea agreement and to amend its provisions. (Article 210 of the Criminal Procedure Code of Georgia)

Oversight over the plea agreement

Plea agreement without the approval of the court does not have the legal effect. The court must satisfy itself that the plea agreement is concluded on the basis of the free will of the defendant, that the defendant fully acknowledges the essence of the plea agreement and its consequences. (Article 212 of the Criminal Procedure Code of Georgia)

A guilty plea of the defendant is not enough to render a guilty judgment. (Article 212 of the Criminal Procedure Code of Georgia) Consequently, the court is obliged to discuss two issues:

• Whether irrefutable evidence is presented which proves the defendant's guilt beyond reasonable doubt.
  
• Whether the sentence provided for in the plea agreement is legitimate. (Article 212 of the Criminal Procedure Code of Georgia).

After both criteria are satisfied the court additionally checks whether formalities related to the legislative requirements are followed and only then makes its decision.

If the court finds that presented evidence is not sufficient to support the charges or that a motion to render a judgment without substantial consideration of a case is submitted in violation of the requirements stipulated by the Criminal Procedure Code of Georgia, it shall return the case to the prosecution. The court before returning the case to the prosecutor offers the parties to change the terms of the agreement. If the changed terms do not satisfy the court, then it shall return the case to the prosecution. (Article 213 of the Criminal Procedure Code of Georgia).

If the court satisfies itself that the defendant fully acknowledges the consequences of the plea agreement, and he or she was represented by the defense council, his or her will is expressed in full compliance with the legislative requirements without deception and coercion, also if there is enough body of doubtless evidence for the conviction and the agreement is reached on legitimate sentence - the court approves the plea agreement and renders guilty judgment. If any of the above mentioned requirements are not satisfied, the court rejects to approve the plea agreement and returns the case to the prosecutor. (Article 213 of the Criminal Procedure Code of Georgia).

Role of the victim in plea agreement negotiations

The plea agreement is concluded between the parties - the prosecutor and the defendant. Notwithstanding the fact that the victim is not party to the criminal case and the prosecutor is not a tool in the hands of the victim to obtain revenge against the offender, the attitude of the victim in relation to the plea agreement is still important.

Under Article 217 of the Criminal Procedure Code of Georgia, the prosecutor is obliged to consult with the victim prior to concluding the plea agreement and inform him or her about this. In addition, under the Guidelines of the Prosecution Service of Georgia, the prosecutor is obliged to take into consideration the interests of the victim and as a rule conclude the plea agreement after the damage is compensated.

Germany

Plea agreements have made a limited appearance in Germany. However, there is no exact equivalent of a guilty plea in German criminal procedure.

Italy

Italy has a form of bargaining, popularly known as patteggiamento but that has a technical name of penalty application under request of the parts. In fact, the bargaining is not about the charges, but about the penalty applied in sentence, reduced up to one third.

When the defendant deems that the punishment that would, concretely, be handed down is less than a five-year imprisonment (or that it would just be a fine), the defendant may request to plea bargain with the prosecutor. The defendant is rewarded with a reduction on the sentence and has other advantages (such as that the defendant does not pay the fees on the proceeding). The defendant must accept the penalty for the charges (even if the plea-bargained sentence has some particular matters in further compensation proceedings), no matter how serious the charges are.

Sometimes, the prosecutor agrees to reduce a charge or to drop some of multiple charges in exchange for the defendant's acceptance of the penalty. The defendant, in the request, could argue with the penalty and aggravating and extenuating circumstancing with the prosecutor, that can accept or refuse. The request could also be made by the prosecutor. The plea bargaining could be granted if the penalty that could be concretely applied is, after the reduction of one third, inferior to five-year imprisonment (so called patteggiamento allargato, wide bargaining); When the penalty applied, after the reduction of one third, is inferior of two years imprisonment or is only a fine (so called "patteggiamento ristretto" limited bargaining), the defendant can have other advantages, like sentence suspended and the effacement of the crime if in five year of the sentence, the defendant does not commit a similar crime.

In the request, when it could be applied the conditional suspension of the penalty according to the article 163 and following of the Italian penal code, the defendant could subordinate the request to the grant of the suspension; if the judge rejects the suspension, the bargaining is refused. When both the prosecutor and the defendant have come to an agreement, the proposal is submitted to the judge, who can refuse or accept the plea bargaining.

According to Italian law, a bargain does not need a guilty plea (in Italy there is no plea declaration); for this reason, a bargaining sentence is only an acceptance of the penalty in exchange with the stop of investigation and trial and has no binding cogency in other trials, especially in civil trials in which parts argue of the same facts at the effects of civil liability and in other criminal trials in which are processed the accomplices of the defendant that had requested and got a bargaining sentence.

Poland

Poland also adopted a limited form of plea bargaining, which is applicable only to minor felonies (punishable by no more than 10 years of imprisonment). The procedure is called “voluntary submission to a penalty” and allows the court to pass an agreed sentence without reviewing the evidence, which significantly shortens the trial. There are some specific conditions that have to be simultaneously met:

• the defendant pleads guilty and proposes a penalty,
• the prosecutor agrees,
• the victim agrees,
• the court agrees.

However, the court may object to the terms of proposed plea agreement (even if already agreed between the defendant, victim and prosecutor) and suggest changes (not specific but rather general). If the defendant accepts these suggestions and changes his penalty proposition, the court approves it and passes the verdict according to the plea agreement. In spite of the agreement, all the parties of the trial: prosecution, defendant and the victim as an auxiliary prosecutor (in Poland, the victim may declare that he wants to act as an "auxiliary prosecutor" and consequently gains the rights similar to official prosecutor) - have the right to appeal.

Japan

In Japan, plea bargaining was previously forbidden by law, although sources reported that prosecutors illegally offered defendants plea bargains in exchange for their confessions.

Plea bargaining was introduced in Japan in June 2018. The first case of plea bargaining under this system, in July 2018, involved allegations of bribery by Mitsubishi Hitachi Power Systems in Thailand. The second case was a November 2018 deal to obtain evidence of accounting and securities law violations against Nissan executives Carlos Ghosn and Greg Kelly.

Under the Japanese system, formally known as the "mutual consultation and agreement system" (協議・合意制度, kyogi-goi seido), plea bargaining is available in prosecutions for organized crime, competition law violations, and economic crimes such as securities law violations. The prosecutor, defendant, and defense counsel each sign a written agreement, which must then be admitted into evidence in a public court without delay.