Neuro Law and Economics
Neuro law and economics is a very young discipline that aims to study law and economics phenomena towards the help of neuroscientific techniques. These studies are the result of bringing together two different approaches that start from different disciplines in order to analyze, in particular, some aspects of the punishment. These two approaches are behavioral and experimental economics and the analyses deriving from the so-called neuro-law. These two disciplines have been developed independently in the last decades and only in the last years they are jointly used to implement scientific analyses of punishment.
Neuro law and economics can be considered as a very young discipline that studies law and economics phenomena towards the help of neurosciences. These studies can be seen as the result of bringing together two different approaches that start from different disciplines in order to analyze, in particular, some aspects of punishment. They implement some experimental and neuroscientific techniques. These two approaches are the studies of behavioral and experimental economics and the analyses deriving from the so-called neuro-law. These two disciplines – that incorporate interdisciplinary approaches – have been developed independently in the last decades and only in the last years they are jointly used to study some scientific phenomena. Then, we have to present these different approaches to understand what neuro (law) and economics is.
Behavioral and Experimental Economics
First of all, we present how the development of Behavioural and Experimental Economics allowed to shed light, among other topics, on the study of punishment in a very new perspective for economists. Let us consider a simple environment as the one represented in the ultimatum game, where we have the presence of two subjects that face a simple economic dilemma. The first player has to choose how to divide a given amount of money between himself and the second player. Then, the second one may or may not accept the choice made by the first one. If the second one accepts the monetary endowment is divided as the first player decided. If the second player does not accept the choice of the first one both the players earn an amount of money that is equal to zero. The classical economic theory predicts that the second player will accept each positive monetary offer from the first one, even if the offer is very unfair. Moreover, the second player is indifferent between the acceptance or the rejection when the first player offers zero. Güth et al. (1982) show – using an the ultimatum game in an economic experiment – that people – the second players – are ready to reject a positive monetary offer if they consider it unfair, even if this choice reduces to zero their monetary endowment. Then, people are ready to spend money to sanction other people if they behave in an unfair way. In particular, Güth et al. (1982) show that people are ready to spend money to sanction an unfair action that damages them. This pioneering result has been confirmed by many other studies in the following decades, also with the implementation of different experimental protocol as the public good game with punishment (Fehr and Gacther 2000, 2002) and the trust – or the investment – game (Berg et al. 1995).
An important ancillary result has been reached after that a new experimental protocol using the third party punishment game has been developed. In his simplest version, in this game we have the presence of three players. A first player can decide how to divide a given amount of money between himself and a second player. After this choice, a third player must decide whether or not to sanction the first one if she/he thinks that the division between the first two players has been unfair. Obviously, the sanction has a positive monetary cost for the third player. Also in this case, the classical economic theory never predicts that a third-party will be ready to spend money to sanction an unfair behavior. As Fehr and Fischbacher (2004) show for the first time, people are ready to sanction an unfair behavior in this case also, even if it damages a person that is not the punisher. Then, they show that people are ready to spend money to sanction an unfair action even if they are not directly damaged by that. Also in this case, other studies confirm this result (see, for instance Henrich et al. (2006) and Marlowe and Berbesque (2007)) also in environments with the presence of a jury that acts as a third party (Ottone et al. 2015).
Obviously, the study of behavior related to sanction is really wide. For a survey on this topic and some suggestions for future research, the readers can refer the paper by Mulder (2016).
Secondly, we have to present the development of neurolaw. In fact, law and science over time had to meet and to confront each other. Scientific discoveries have always raised a strong international juridical debate. From this meeting and clash between law and science, more or less suddenly, innovations and changes arise into legal system. Suffice it to think to legal issues about the declaration of human death or when we have before us a brain death. Other examples could be permission to use new informatics technologies inside the courtrooms or to use biological evidences such as blood or DNA trails.
Neurolaw stems from this continuous debate between law and science, particularly from Neuroscience.
Neuroscience is a discipline that studies the nervous system. It arises from the relationship of biology with medicine, psychology, mathematics, engineering, chemistry, thus evolving as an interdisciplinary science. Aim of neuroscience is to understand how the interconnections among single nervous cells (neurons) produce different perceptive and motors acts and different cognitive processes such as decision making or problem solving.
In the last years of 1900 different disciplines apparently unrelated to neuroscience begin to incorporate into their researches neuroscientific data and methodologies giving rise to new disciplines such as Neuroeconomic, Neuromarketing, or Neuroesthetics.
Neurolaw explores the effects of neuroscientific discoveries on legal rules (Petoft 2015) investigating law-relevant mental states and decision-making processes in defendants, witnesses, jurors, and judges.
Aim of law is to regulate individual’s conducts, to respect human dignity, and to create a just and fair legal system. Moreover, law judges evidences about the causes of human behaviors, and neuroscientific study of human brain functions can make a very important contribution, so that the interaction/integration of neuroscientific discoveries in Law is inevitable.
The term “neurolaw” first appeared in 1991 in a scientific paper by Taylor et al. entitled “Neuropsychologists and Neurolawyers.” In this paper, Taylor and his co-authors analyzed how neuroscience, and in particular Neuropsychology, could provide probative data during a trial with defendants with cerebral lesions.
In subsequent years, thanks to the advent of new technique of neuroimaging such as functional magnetic resonance imaging (fMRI) or the not invasive technique of brain stimulation such as transcranial magnetic stimulation (TMS) and Transcranial Direct Current Stimulation (TDCS), the attention to neurolaw increased. In 2007, Law and Neuroscience Project was born from The John D. and Catherine T. MacArthur Foundation. The interdisciplinary project has the goals to help the legal system in order to avoid an improper use of neuroscientific evidence in some law contexts. Furthermore, it tries to deploy neuroscientific insights to improve the fairness and effectiveness of the criminal justice system.
The neuroscientific techniques usually adopted in neurolaw are electroencephalography (EEG), fMRI and TMS and TDCS. EEG is a not invasive technique which measures brain activity during the rest or during some cognitive tasks towards the information provided by superficial electrodes placed on various regions of the scalp.
fMRI is a correlational methodology which enables to detect the so called BOLD (blood oxygenation level dependent) signal. It is an indirect measure of neural activity and represents a small change in the levels of oxygenated red blood cell when a muscular or mental activity is performed. This technique is very useful because it is characterized by a high spatial resolution (the identification of volumetric area of 3 mm).
TMS and TDCS are causal methodologies, which enable to interfere with the cerebral activity and to observe functional changes. The first uses the electric field elicited by a magnetic field, and the second uses low intensity of electric current. Both have a moderate spatial resolution and TMS has an optimal temporal resolution.
It is possible to identify several topical areas on which the research of neurolaw scientists is focused.
Mind Reading or Lie Detection
To detect deception and truth in an individual is the dream of many judges. The use of lie detector tests has become a popular and legendary symbol from crime dramas to comedies to advertisements. The lie detector test provides for the use of three physiological signals recorded with a Polygraph: heart rate/blood pressure, respiration, and skin conductivity. Courts, including the United States Supreme Court, had repeatedly rejected the use of Polygraph because of its inherent unreliability.
Recently EEG method was employed in two forensic techniques: Brain Fingerprinting (BF) and Brain Electrical Oscillations Signature (BESOS) (for a description of these technique see Chauhan (2016) and Puranik et al. (2009)). The first was admitted in 2003 in a legal proceeding of Terry Harrington in Iowa. BF detects particular brain waves called p300. According to its inventor Lawrence Farwall (neuroscientist at Harward university), these waves are correlated to memories of the past. Terry Harrington was sentenced to life for a murder, but defense subjected him to BF which resulted in a negative outcome, as if memories of the murder were not in his memory. Iowa District Court admitted BF test as scientific evidence and the murder case was re-opened. Later Terry Harrington was acquitted after the confession of a key witness. The case of Terry Harrington is the first and only one where a Court admitted the BF test. This is relevant because, although the BF has not been exposed to a peer review, its admission challenges previous judgment. This case is the proof that a neuroscientific evidence can influence the judge’s decision making.
Different neuroscientific researches investigated the brain networks that underlie lie production (Meijer et al. 2016 for review). fMRI is the most used method and it is employed by several companies such as No Lie MRI. Some studies conducted by Daniel Langleben showed how lies are distinguished from truth by increased prefrontal and parietal activity (Langleben et al. 2005). Although numerous fMRI neurolaw researches on lie detection are continuing, the Courts still exclude fMRI lie detection evidence from trials. As an example, Judge Eric M. Johnson of the Maryland Sixth Judicial Circuit had refused to admit potential exculpatory fMRI evidence during the murder trial of State v Gary Smith, claiming that “the use of fMRI to detect deception has not achieved general acceptance in the scientific community”(MacArthur Foundation 2016).
In fact, fMRI studies have different general limitations: because of its correlational nature, this methodology cannot be used to prove causation. When an fMRI study shows that a brain region is active when a person is trying to lie, one cannot exclude that the same brain region might be active because it is involved and activated during a state of anxiety or in any other cognitive processes. One meta-analysis study showed that the regions usually related to deception were the ventrolateral and dorsolateral prefrontal cortex, inferior parietal lobe, anterior insula, and medial superior frontal cortex (Christ et al. 2009). These brain regions are also activated during general executive processes as planning, working memory, and emotional process. Therefore, a limitation is to discern whether the neural activity measured by fMRI is associated with lying or with other neural processes. Moreover, many scientists argue that lie detection data recorded with fMRI are valid only within the context of controlled laboratory experiments, which often poorly approximate the real word.
Neuroscientists agree that more studies are needed before starting to use fMRI lie detection methodology.
Differently from fMRI, MRI was frequently admitted in courtrooms when it is relevant to obtain behavioral information correlated to specific brain pathologies. In 2007 a court of New York have authorized the scan of the defendant’s brain, the popular journalist Peter Braunstein indicted of kidnapping and sexual assault. The defense intended to show that the brain illness “Schizophrenia” might have made it difficult for its client to control violent impulses. At the end of the trial, Braustein was utterly convicted: this case demonstrates how a neuroscientific evidence can be useful but not necessarily lead to acquittal. Neuroscientific evidence could be able to indirectly address questions of intent in defendants with neurological or psychological illness that might reduce the ability of judgment during the crime. Another important contribution of neurolaw regards the brain development in adolescence. In fact, neuroscientific evidence has demonstrated that the adolescent brain has a slow development of the cerebral regions necessary for cognitive control as Prefrontal cortex (Blakemore and Robbins 2012). For this reason, adolescence is characterized by low risk aversion and impulsiveness. The contribution of neuroscience to law about the behavior of adolescents brought in 2005 the US supreme court to the abolition of the death penalty.
Another important contribution of neuroscience to law is represented by studies on memory focused on memory limitations. These limitations may affect not only witnesses but also juries.
Bringing Together Behavioral and Experimental Economics and Neurolaw
Now neurolaw researches also deal with neuroscience evidence to understand and to improve decision making of the judge. Human societies universally expect that criminals will be punished, usually by impartial third-party decision makers. Then, the integration of Neurolaw together with behavioral economics can use various experimental protocols to investigate the punishment. Obviously, paradigms commonly used by neuroscientist are those used by experimental economists such as the third-party punishment or the hypothetical crime scenarios. The first is the economic game presented before where a potential punisher, the third-party, observes how a dictator share an amount of money with a receiver. In this case he may choose to punish the dictator spending his money or he can simply observe the scene. In this case, neuroscientific tools can be used to observe what happens in the brain of the three players. In the second paradigm, the subjects make various decisions about some different scenarios where a crime can be committed. These paradigms are used together with neuroscientific methodologies as fMRI or not invasive brain stimulation (TMS, TDCS) in order to investigate the neuronal underpinning of punishment. The data showed different brain networks, with an involvement of anterior Insula and dorsal and anterior cingolate cortex and Amigdala. This first network seems to be involved in the detection of norm violation (Sanfey et al. 2003; Krueger and Hoffman 2016). A second network is formed by medial prefrontal cortex, ventromedial and dorsomedial prefrontal cortex, posterior cingulate cortex, and tempo parietal junction. The second brain network connected to the first one is generally associated to self-monitoring, mentalizing (Bressler and Menon 2010), emotional processes related to the harm to the victim. Both networks are connected to a central executive network engaging posterior parietal cortex and dorsolateral prefrontal cortex. The central executive network underlies the final decision making and then selects a specific punishment, integrating the information processed in previous networks with the contextual facts as circumstances surrounding the crime. The neuroscientific evidence about punishment could elucidate the neuronal and contextual variables that can influence the decision making.
Moreover, Neuroeconomics, another neuroscientific discipline, helps the juridical system and several times neuroeconomic studies are borderline with neurolaw studies. Pisoni et al. (2014) in a TMS study assessed that fair or unfair economic decisions, and context, in terms of different interaction styles, may modulate the corticospinal excitability. Authors show that economic exchange, indeed, especially when imposed by only one part (proposer), can elicit positive or negative emotions according to the context in which it occurs, implying different moral evaluation and reactions. These results are very important for a legislator and for policy, because explore the people’s reactions to injustices.
Although there are the a number of studies about legal decision making, lie detection, mind reading, and criminal responsibility, legal experts and lawyers still try to understand the best way to integrate neuroscience, behavioral economics, and law. Today, the best neuroscientific data that neurolaw can deliver to law are the evidence about criminal responsibility of individuals with neurological diseases. Some neurological pathologies indeed can elicit different criminal behaviors, especially diseases caused by damage to frontal brain areas involved in control of instinctive behaviors and decision making. The other topics of neurolaw so far have not gained scientific validations external to laboratories. The law is good to be prudent. Anyway interdisciplinarity will lead us to the law of future.
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