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ETHICAL ISSUES RAISED ETHICAL ISSUES RAISED

BY NEUROSCIENCE IN LAWBY NEUROSCIENCE IN LAW

By Walter SinnottBy Walter Sinnott--ArmstrongArmstrongPhilosophy Department andPhilosophy Department and

Kenan Kenan Institute for Ethics at Duke,Institute for Ethics at Duke,

Uehiro Uehiro Centre for Practical Ethics at Oxford,Centre for Practical Ethics at Oxford,

MacArthur MacArthur Law & Neuroscience ProjectLaw & Neuroscience Project

•• Law and neuroscience (or Law and neuroscience (or neurolawneurolaw) )

studies legal issues raised bystudies legal issues raised by recentrecent

neuroscience and many waysneuroscience and many ways that that

neuroscience neuroscience shouldshould and and should notshould not

be used withinbe used within the lthe legal system.egal system.

•• The legal systemThe legal system includesincludes courts, courts,

legislatures, prisons, parole boards, legislatures, prisons, parole boards,

and police stations.and police stations.

What is Law and Neuroscience?

Brain scans could be used in legal trialsBrain scans could be used in legal trials

to detect current mental states:to detect current mental states:

1.1. Lies by witnessesLies by witnesses

2.2. Memories of witnesses (and jurors?)Memories of witnesses (and jurors?)

3.3. Bias in jurors (and judges?)Bias in jurors (and judges?)

4.4. Pain in plaintiffs seeking tort damagesPain in plaintiffs seeking tort damages

5.5. Consciousness inConsciousness in cases of euthanasiacases of euthanasia

Uses of Neuroscience in Trials

Brain scans could also be used in legalBrain scans could also be used in legal

trials to assess mental trials to assess mental abilitiesabilities affecting:affecting:

1.1. ResponsibilityResponsibility of adolescentsof adolescents and and

defendants with brain damagedefendants with brain damage,, addiction, addiction,

mental illness, mental illness, psychopathypsychopathy, , ... ...

2.2. CompetenceCompetence to stand trial or to maketo stand trial or to make

life decisionslife decisions



Neuroscience could be used in legal trials Neuroscience could be used in legal trials toto predictpredict future behavior relevant to:future behavior relevant to:

•• SentencingSentencing

•• ParoleParole

•• Involuntary commitmentInvoluntary commitment or detentionor detention

Neuroscience could be used inNeuroscience could be used in legal trials legal trials to to enhanceenhance memory, attention, and other memory, attention, and other cognitive abilities in:cognitive abilities in:

WitnessesWitnesses

JurorsJurors


Case #1

�� Imagine being accused of robbery.Imagine being accused of robbery.

�� You know that you are innocent.You know that you are innocent.

�� A witness says that he saw youA witness says that he saw you do it. do it.

�� You have no alibi or other counterevidence.You have no alibi or other counterevidence.

�� Your lawyer tells you that a new method ofYour lawyer tells you that a new method of

lie detectionlie detection is accurate 95% of the time.is accurate 95% of the time.

�� Your defense attorney asks the judge to let Your defense attorney asks the judge to let

him test the witness and you.him test the witness and you.

Case #2

�� Imagine being robbed.Imagine being robbed.

�� You identify the defendant.You identify the defendant.

�� HisHis friend testifies that they were friend testifies that they were elsewhere during the robbery.elsewhere during the robbery.

�� The prosecutor knows about accurate The prosecutor knows about accurate neural lie detection.neural lie detection.

�� The prosecutor asks the judge toThe prosecutor asks the judge toallow himallow him to test the friend and you.to test the friend and you.

What is a Lie?What is a Lie?

�� People lie when they say something People lie when they say something they know is false with the intention they know is false with the intention to to deceive and usually to induce reliance. deceive and usually to induce reliance.

�� To show someone is lying, a method To show someone is lying, a method needs to detect knowledge and intent. needs to detect knowledge and intent.

�� ThereThere’’s no way to do show this directly. s no way to do show this directly. All tools use indirect accompaniments.All tools use indirect accompaniments.

�� Torture, drowning, and meatballsTorture, drowning, and meatballs

�� CrossCross--examinationexamination

Pre-scientific Lie Detection

�� Skin conductance response (SCR)Skin conductance response (SCR)

�� Systolic blood pressureSystolic blood pressure

(possibly in conjunction with drugs,(possibly in conjunction with drugs,

such as such as amobarbitolamobarbitol))

Polygraphs

�� 1 1 –– periorbital thermographyperiorbital thermography

�� 2 2 –– micromicro--facial expressionsfacial expressions

�� 3 3 –– nearnear--infrared infrared lasar lasar spectroscopyspectroscopy

�� 4 4 –– electroencephalography (EEG)electroencephalography (EEG)

�� 5 5 –– fMRIfMRI

More Scientific Lie DetectionMore Scientific Lie Detection

�� EEG (Brain Fingerprinting and BEOS)EEG (Brain Fingerprinting and BEOS)

�� fMRI fMRI ((Cephos Cephos and No Lie MRI)and No Lie MRI)

Neural Lie Detection

Brain FingerprintingBrain Fingerprinting

�� Uses EEG (electroencephalography)Uses EEG (electroencephalography)

�� Developed by Lawrence FarwellDeveloped by Lawrence Farwell

�� Sold by Brain Fingerprinting LabsSold by Brain Fingerprinting Labs

(www.(www.brainwavesciencebrainwavescience.com).com)

QuestionsQuestions

�� 1 1 –– Is this really lie detection?Is this really lie detection?

�� 2 2 –– How reliable is it?How reliable is it? Labs are not Labs are not realistic circumstancesrealistic circumstances

Brain Fingerprinting in CourtBrain Fingerprinting in Court�� On March 5, 2001, Iowa District Court Judge Tim On March 5, 2001, Iowa District Court Judge Tim

O'Grady ruled that Brain FingerprintingO'Grady ruled that Brain Fingerprinting®® testing is testing is admissible in court.admissible in court.

�� Dr. Farwell conducted a Brain Fingerprinting test on Dr. Farwell conducted a Brain Fingerprinting test on Terry Harrington, who was serving a life sentence in Terry Harrington, who was serving a life sentence in Iowa for a 1977 murder.Iowa for a 1977 murder.

�� The test showed that the record stored in Harrington's The test showed that the record stored in Harrington's brain did not match the crime scene and did matchbrain did not match the crime scene and did matchthe alibi.the alibi.

�� On February 26, 2003, the Iowa Supreme Court On February 26, 2003, the Iowa Supreme Court reversed Harrington's murder conviction and orderedreversed Harrington's murder conviction and ordereda new trial.a new trial.

India 2008India 2008

�� Uditi Uditi and and Pravin Pravin meet in McDonald Hotelmeet in McDonald Hotel

�� Pravin Pravin later dies from cyanide.later dies from cyanide.

�� There was evidence (cyanide on There was evidence (cyanide on UditiUditi’’s s purse), but there purse), but there

was not enough evidence to convict, until she volunteered was not enough evidence to convict, until she volunteered

to take neural lie detection.to take neural lie detection.

�� BEOS technique based on FarwellBEOS technique based on Farwell’’s researchs research

�� The test came out positive for lying.The test came out positive for lying.

�� Uditi Uditi was convicted and sentenced to life in prison.was convicted and sentenced to life in prison.

�� She was recently given a new trial.She was recently given a new trial.

�� Is this evidence good enough? Finding guilt Is this evidence good enough? Finding guilt vsvs. innocence. innocence

fMRI fMRI Lie DetectionLie Detection

�� No Lie MRINo Lie MRI was started by Joel was started by Joel Huizenga Huizenga andand

is located in La Jolla, CA. Its methods are based is located in La Jolla, CA. Its methods are based

on work by Daniel on work by Daniel Langleben Langleben at University of at University of

Pennsylvania. See http://www.Pennsylvania. See http://www.noliemrinoliemri.com/.com/

�� CephosCephos isis run by Steven run by Steven Laken Laken and is located and is located

in Boston, MA. Its methods are based on in Boston, MA. Its methods are based on

research by Andrew research by Andrew Kozel Kozel and Mark Georgeand Mark George

at the Medical University of South Carolina.at the Medical University of South Carolina.

See See http://www.http://www.cephoscorpcephoscorp.com/.com/

The Main ProblemThe Main Problem

Do circumstances in labs where neural lie Do circumstances in labs where neural lie detectiondetection works works resemble resemble circumstances of real trialscircumstances of real trials in relevant in relevant ways?ways?

That depends on wThat depends on what exactly the neural hat exactly the neural method is detecting.method is detecting.

Since this is not clear, we need to guess:Since this is not clear, we need to guess:

NervousnessNervousness

1.1. People get nervous when they People get nervous when they lie,lie, so maybe neural methods so maybe neural methods testtest when peoplewhen people are nervous,are nervous,but witnesses get nervous even but witnesses get nervous even whenwhen they tell the truth in trials.they tell the truth in trials.

InhibitionInhibition

2.2. People have a natural impulse toPeople have a natural impulse totell tell the truth that they must inhibit the truth that they must inhibit when when they they lie, lie, so neural methods so neural methods might test might test when people inhibit such when people inhibit such impulses.impulses. However, However, lawyers advise lawyers advise witnesses to suppresswitnesses to suppress their impulse their impulse to blurt out answers even whento blurt out answers even whenthey are telling the truth.they are telling the truth.

Kinds of MemoryKinds of Memory

3.3. People who were at the crime have People who were at the crime have episodicepisodic memories of being therememories of being thererather than just rather than just semanticsemantic memoriesmemoriesthat it happened, so maybethat it happened, so maybe neural neural methods test for episodic memories,methods test for episodic memories,but episodic memories can be but episodic memories can be triggeredtriggered by pictures, imagined by pictures, imagined experiences,experiences, similar memories,similar memories,and so on.and so on.

Conclusions on Lie Detection Conclusions on Lie Detection

�� No method of neural lie detectionNo method of neural lie detection so far is so far is

reliable enough for courtroom use.reliable enough for courtroom use.

�� In the future, burden of proof will become crucial:In the future, burden of proof will become crucial:

–– Criminal prosecution needs to establish defendantCriminal prosecution needs to establish defendant’’s s

guilt beyond a reasonable doubt.guilt beyond a reasonable doubt.

–– Defense only needs to show reasonable doubt.Defense only needs to show reasonable doubt.

–– Businesses, government agencies, andBusinesses, government agencies, and private people private people

do not need to prove claims beyond reasonable doubt.do not need to prove claims beyond reasonable doubt.

Are Brain Scans Are Brain Scans DangerousDangerous??

Even if neural lie detection is probative Even if neural lie detection is probative

and also somewhat reliable,and also somewhat reliable, it still should it still should

not be admitted into trials if it is not be admitted into trials if it is

““prejudicialprejudicial””..

A series of studies suggest that brain A series of studies suggest that brain

images are likely to mislead or confuse images are likely to mislead or confuse

many jurors.many jurors.

Are Brain Scans Are Brain Scans DangerousDangerous??�� Bright & Bright & GoodmanGoodman--Delahunty Delahunty (2006)(2006)

QuickTime™ and aTIFF (LZW) decompressor

are needed to see this picture.

Are Brain Scans Are Brain Scans DangerousDangerous??�� Weisberg, Skolnick, et al. (2008)Weisberg, Skolnick, et al. (2008)



Are Brain Scans Are Brain Scans DangerousDangerous??Weisberg, Skolnick, et al.

(2008)

Are Brain Scans Are Brain Scans DangerousDangerous??

“Watching TV helps with math ability because both activate the temporal lobe.”

McCabe and Castel 2007

Are Brain Scans Are Brain Scans DangerousDangerous??•Gurley & Marcus (2008)



Do Brain Scans Do Brain Scans InformInform??

Even if brain images change verdictsin juries, how can we tell whether

the brain images

(1) mislead or confuse instead of(2) helping juries reach more

accurate verdicts?

What about What about Real Real JuriesJuries??

Unlike lab subjects:Real jurors are not all college students.

Real jurors hear more details of each case.

Real jurors know real lives are affected.

Real jurors hear both sides of argument.

Real jurors deliberate and are accountableto other jurors for giving reasons.

Would Brain ScansWould Brain Scans MisleadMislead

or or ConfuseConfuse Real Real JuriesJuries??To answer this question, we need to ask

(a) people who might be on juries(b) to decide realistic legal cases

(c) of various kinds

(d) in realistic circumstances (cross

examination, group deliberation)(e) with and without brain images.

Scientific ConclusionsScientific Conclusions

At present, neural lie detection and brain images

are only minimally probative (& minimally reliable).

At present, we have some reason to suspect that

brain images bring dangers of misleading and

confusing juries (and maybe also judges).

Legal ConclusionsLegal ConclusionsIf functional brain images are even moderately

misleading or confusing, then their dangers

substantially outweigh their probative value.

If so, they fail the balancing test of US FRE 403.

If so, they should not be admitted as evidence.

If so, a temporary moratorium on functional brain

images in trials would be justified under current law.

A Worry: Burden of ProofA Worry: Burden of Proof

�� In criminal trials, the prosecution usually In criminal trials, the prosecution usually needs to prove each element of guiltneeds to prove each element of guiltbeyond any reasonable doubt.beyond any reasonable doubt.

�� Even if functional brain images are only Even if functional brain images are only minimally probative, if they have not yet minimally probative, if they have not yet been shown to be prejudicial, then maybe been shown to be prejudicial, then maybe courts should give leeway to defense.courts should give leeway to defense.

�� This decision isThis decision is a matter of ethics and, a matter of ethics and, hence, is for law and society, not scientists.hence, is for law and society, not scientists.

ThatThat’’s all,s all, folks.folks.

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