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Let's talk about the role of psychology in law

Will and Timothy are joined by guest Dr. Jason Chin, for a chat about the relationship between psychology and law.

In this chat format, we gather regular authors and guests in Slack and have a moderated conversation, guided by prompts and questions selected in advance. Participants get to respond to each other's points, make comments, and ask each other questions in real-time.

The transcript has been lightly edited.



Will Crozier 🐙
Welcome to another Exercise in Exceptions chat! We’ve talked a lot about how psychology research can influence the law – but that research needs to make it into the courts to actually make the intended difference. However, it’s never as easy as explaining a study or two to a jury. In this chat, we’re going to discuss this collision a bit – how psychology science is used in the legal system.

Timothy and I are joined by Dr. Jason Chin, a lecturer at the TC Beirne School of Law at University of Queensland, Australia. Welcome, Jason!

Jason
Thanks for having me!

Will Crozier 🐙
Would you mind giving us a bit of an introduction for yourself?

Jason
Thanks, Will.  No problem. I finished a PhD in social psychology at the University of British Columbia in 2010. I did a bit of research on memory there and some research on morality. Then I decided I hate money so I went to law school at the University of Toronto after that. I practiced for about two years and then started as a lecturer here in Queensland last year. I mainly write and publish about law and psychology. And that's mainly in the field of evidence law, because there is a lot of psychology built into those rules.
Jason Chin

Will Crozier 🐙
When you saw you practiced law - were you a trial attorney? Actually making objections and telling people they can't handle the truth?

rabbitsnore (Timothy Luke)
Point of interest: It was a witness, not a lawyer, in A Few Good Men who made that declaration.

Jason
Sort of. I was in the litigation group but I only actually made it to court once. I probably should have gotten into criminal law or a boutique where I'd get to actually go to court. But I was in a large firm where most of the matters were so complex that juniors couldn't go to court on their own, or if they did get to go, just assist.

And that actually is true about Jack in A Few Good Men.

Will Crozier 🐙
True, true -I'll make sure I rewatch any movies I reference in chat before bringing them up from now on

Timothy, we know you don't have a JD and aren't a lawyer...but you've had a bit of experience with bringing psychology into the legal system, right?

rabbitsnore
A bit, yes. I've consulted on a number of cases of disputed confessions (i.e., confessions in which the defense argues coercion or unreliability). I'm also author on a recent survey of experts on the psychology of confessions1, in which we attempt to establish what parts of the research are "generally accepted" in the scientific community -- which is an important legal standard in many jurisdictions, concerning whether an expert is permitted to testify.

Jason
I'd love to see the results of that!

rabbitsnore
I'll send you a copy!

Jason
Thanks!

What would you say to the argument that since the jury can see the tape of the confession in most places now, that there's no need for an expert on that topic.

rabbitsnore
I'm not sure it's most places -- but it's many more than it used to be. Showing the tape is useful, but much of the psychology of interrogations and confessions is counter-intuitive, so I think expert testimony is quite useful, even if there's a recording and the jury can see it.

Will Crozier 🐙
That's a good example, I think, of an overall question that I think is worth explicitly addressing: Why should the courts care about psychological science? Jason, as our guest, why don't you take the first answer?

Jason
For a lot of reasons! Psychology bears on the reasons we have rules, the way the rules work, and the way our courts work. For instance, there’s a naïve psychology in most evidence rules. Consider the rule against character evidence. It appears that the rule makers donned their psychology hats and assumed that juries would fall into the fundamental attribution error* and judge parties based on their character. And so they banned this type of evidence, subject to exceptions.

As for psychology as evidence in courts (rather than as the basis for the rules), your readers should check out Monahan and Walker, who are really the OGs in this area. They divided this into social science bearing on legislative facts versus** adjudicative facts 2,3,4
Legislative facts go beyond the dispute itself, such as if the death penalty actually acts as a deterrent.

Adjudicative facts bear only or primarily on the dispute at hand, such as if the accused was suffering from a mental disorder.

rabbitsnore
I hadn't ever thought about character evidence in that way. Do you think there's something similar going on with, say, the idea that evidence should be "more probative than prejudicial"?

Jason
I think that psychology often defines what we consider to be the prejudice. For instance, courts will often exclude grizzly photographs of the crime scene. If the manner of death is not disputed then there's little probative value. But it's very prejudicial because, according to their logic, the passions of the jury are so inflamed that they will seek a conviction regardless of the other facts.

rabbitsnore
To some extent, that assumption has borne out in research, such as that by Jessica Salerno.
She's conducted experiments showing that gory photos can increase the propensity to vote guilty.

Jason
It does make sense. There's also some research about if brain scans are overly prejudicial (and it's found they are not). That's Francis X. Shen's research5.

Will Crozier 🐙
What do you think, Timothy? Why should the courts pay attention to psychological science?

rabbitsnore
Many of the judgments and decisions made in court are essentially psychological. That is, there are loads of legal processes or functions that psychological science can help inform. For example, triers-of-fact, judges, and lawyers regularly need to assess the credibility of witnesses or make judgments about whether someone is being deceptive. We have lots of psychological research on what kinds of evidentiary and extra-evidentiary variables can influence people’s credibility judgments. Research like this can help in a few different ways. It can, for example, help an attorney strategize about whether a witness is likely to be believed by a juror. And it can also help shape legal decision-making by disabusing people of mistaken beliefs.

Psychological science is especially important when research findings conflict with common sense or prevailing legal thinking (and this happens a lot). A prominent example is false confessions, which can be highly counterintuitive. Another example is deception detection – that is, catching lies. Most legal actors seem to have implicitly or explicitly stereotypical views about deception and how to detect it (e.g., in body language, signs of anxiety, or facial expressions) – and those beliefs do not stand up to scientific scrutiny.

Jason
I've spoken to many judges and lawyers about this, and despite all the empirical evidence, they still think they can tell when someone is lying. Maybe it's some sort of Dunning-Kruger Effect***.

rabbitsnore
Yeah, it's a belief that's hard to kill.

Jason
The partners at my old firm were also convinced that after a few minutes in a room, they could tell if a job candidate would be a great lawyer one day.

rabbitsnore
That seems... unlikely.

Will Crozier 🐙
Well, there is a bit of research on thin slicing

rabbitsnore
I was about to bring that up.

Jason
What is it?

Will Crozier 🐙
That is, people can make decisions just as accurately after very short times and little information, as they can after longer times and more information, sometimes even more accurately

Jason
What moderates that?

rabbitsnore
When those judgments or decisions have to do with other people, though, it's mostly in the domain of, like, assessing how well people are going to get along. That is, you can often get as good sense of how someone is going to behave in social situations from a small sample of their behavior than from spending a lot of time with them6. But that doesn’t always make someone better.  People aren't good at catching lies, regardless of how much time they have to observe someone7.

Will Crozier 🐙
I think it's a bit of a reach to go from a couples therapist thin-slicing relationship success, to assuming people can thin-slice more complex decisions, like guilt, lie detection - or whether someone will make a good attorney

That kind of underlines the importance of good research though, by making sure we know the limits of certain phenomena and intuitions

One thing I'm curious about is what ways you guys think attorneys and psychologists might differ in how they look at the role of psychology in the legal system

Jason, you probably have a good idea of this, given you worked in a law firm, but have a phd in psychology yourself

Jason
I may!

I think lawyers will tend to look at it more naively and instrumentally. Lawyers want the best outcome for their client and thus they will seek out psychological evidence if it supports their client’s position. I do think they are a bit naïve about how psychological science is actually conducted. For instance, I think many aren’t aware of reproducibility issues and the move to open science.

I think psychologists are a bit naïve about how courts will actually view the psychology. For instance, there may be a tendency to think that if the science is reliable and relevant to the case, then it should be admitted. However, courts have several considerations. For instance, they may exclude evidence if they think they can cover it in their directions to the jury. And they are also very aware of evidence taking up too much time or being overly persuasive to the jury (i.e., usurping the role of the trier of fact).

rabbitsnore
Is evidence taking up too much time a legally acceptable reason to exclude it? Perhaps I'm betraying my own naivety as a psychologist when I say this, but that seems like the kind of rationale that could easily lead to reversal on appeal.

Will Crozier 🐙
Right - as psychologists, we're trained to collect as much information as possible...the more we have, the clearer a picture we get

But to some extent, the courts need to balance completeness with timeliness, right? (he asks, a naive psychologist)

Jason
I suppose that'd be more of an issue if goes to a relatively minor issue at trial. But it is listed as a consideration in the legal tests I'm familiar with. I guess the idea is that the jury can only really absorb so much.

I can quote from the leading case in Canada "Evidence that is otherwise logically relevant may be excluded on this basis, if its probative value is overborne by its prejudicial effect, if it involves an inordinate amount of time which is not commensurate with its value or if it is misleading in the sense that its effect on the trier of fact, particularly a jury, is out of proportion to its reliability." 8

rabbitsnore
In principle, that seems reasonable to me: balance the value of the evidence against the resources it will consume to present it.

Will Crozier 🐙
What do you think, Timothy - have you noticed any disagreements with any of the attorneys you've worked with?

rabbitsnore
I have... My experience suggests to me that attorneys often don’t have a clear sense of what psychologists do. For example, I’ve had attorneys call me and ask me to do clinical evaluations of their clients. I am totally unqualified to do that. I can’t perform clinical evaluations of any kind. Attorneys are sometimes surprised when I tell them I can’t. I can provide consultation and testimony about, say, risk factors associated with false confessions – but I can’t run tests on a defendant. To some extent, this is understandable. A lot of people don’t know the difference between a clinical psychologist and a psychological scientist.

A lot of attorneys probably have a very clinical view of psychology. That is, they probably think that psychologists are potentially useful experts if there is, say, a risk that their client is cognitively impaired or mentally ill. And there are, of course, psychologists with expertise in those areas. But there are also psychologists who know a lot about interrogations, memory, confessions, and deception. Psychological scientists in the latter category are probably underused as witnesses largely because many attorneys may simply be unaware of their existence, of what they know, or of how what they know could be relevant to their cases. Psychologists have a lot of unused potential as sources of expert evidence.

Jason
I think that is a misconception about psychology more generally - that it's all clinical work. But actually, Will and I had to deal with a case in a paper we just finished in which the judge expressly said that he wasn't sure memory research was an established field of psychology. Unfortunately, that's the leading case on admitting memory experts in Canada - R v McIntosh9.

rabbitsnore
Wait... Memory research in general?

He wasn't sure if memory research was a thing at all?

Jason
Here's the quote: "As is implicit in what I have written above, I have some serious reservations as to whether the "Psychology of Witness Testimony" is an appropriate area for opinion evidence at all. I acknowledge that the subject is interesting and Dr. Yarmey's presentation is informative. I also applaud his evidence that he lectures on the subject to police officers. We should all be reminded of the frailties of identification evidence. However, I would have to be persuaded that the subject is a recognized branch of psychology."

He was talking about eyewitness memory research.

rabbitsnore
The psychology of testimony is literally one of the oldest branches of psychology.

Jason
And Yarmey is a great guy!

Will Crozier 🐙
Not all psychologists are Hannibal Lecter...both in terms of professional interest and....leisure interest

Jason
...but some are 😉

rabbitsnore
Point of interest: Hannibal Lecter was a psychiatrist.

Jason
I was implying that I'm a cannibal.

rabbitsnore
Yeah, I got that. Heh.

Will Crozier 🐙
Was in the PhD or the JD that pushed you to such desperate measures? Interested readers want to know!

Jason
I actually talk about Jon Haidt's research**** on this in my psych and law class. It's hard to explain why it'd be wrong to eat your dead parent if there aren't any disease issues. And to what extent are legal decisions just post-hoc rationalizations of moral intuitions?

Will Crozier 🐙
Well that's a bit of a discomforting thought

rabbitsnore
My guess is that many legal decisions are exactly that.

Jason
Me too!  But some of the law students have Will's reaction!

Will Crozier 🐙
The quote about Dr. Yarmey's leads to another question...what do you think is a misconception that the courts have about psychological research?

Timothy, any you've noticed beyond what you've already mentioned about experimental vs clinical research?

rabbitsnore
My answer is going to be broad and provocative…

I suspect that courts have the same misconceptions about psychological science that a lot of people have. That is, that psychology is not scientific. Or if it is, that it is somehow “softer.” Many people have the implicit or explicit belief that human thought, emotion, and behavior is somehow outside of science’s purview. It’s true that psychology is a young science (only a couple hundred years old) and that our measurements are often very imprecise.

At the risk of simply going on a rant, it’s a source of unending frustration to me that some pseudosciences are unblushingly permitted into courts as evidence, while solid psychological science is often excluded. Every time I hear about someone claiming they can identify a person based on a bite taken out of a sandwich or something, I want to pull my hair out – not just because the “scientific” claims are nonsense but because courts often exclude psychology on the basis of it being insufficiently scientific. If the bar is set so low that someone can testify that a gunshot wound was likely caused by two people pulling the trigger of the gun at the same time, I don’t see why psychology isn’t allowed into court more frequently. The reality is that psychology is – in spite of its many blemishes – is frequently based on far more rigorous methods than forensic science. (I hasten to add that not all domains of forensic science are bankrupt, of course. DNA evidence, for example, is solid when it’s done right.)

This is admittedly speculation, but my guess is that courts often don’t take psychology seriously in large part because of simple stereotypes about what science looks like. Identifying a person from a bite mark seems like the sort of thing science should be able to do. To many people, identifying the conditions under which people falsely confess doesn’t seem like the sort of thing science can do.

In short, I think courts have misconceptions about what science can and cannot do, both in general and about psychology in particular.

Jason
I tend to agree with you Timothy. And this is something that Will and I also tackle in that paper. We've seen a lot of decisions like the Yarmey one where the court expresses the belief that social and cognitive psychology are common sense. These typically have to do with psychology that would discuss memory errors and the situational forces causing wrongful confessions. It seems like courts here are being dispositionist – undervaluing the situational and unconscious forces that impact our behaviors and conscious thoughts.

But let me play devil's advocate for a second.

Will Crozier 🐙
By all means!

Jason
One thing that may distinguish the forensic bite mark cases you mention is that they would give information about the case itself. They are about that particular bitemark. But all memory or confession research could do is explain the factors that may have been at play. You cannot opine with any degree of confidence about the reliability of a particular memory or confessions.

rabbitsnore
If I were testifying, that's right. I wouldn't speak to the "ultimate issue" of whether a confession or memory or eyewitness identification was reliable. But there are things that (other) psychologists might do that have more direct implications for a given case. For example, a clinician could evaluate a defendant for cognitive impairments, malingering, or mental illness -- and those factors could have fairly direct legal implications, both for fact-finding and sentencing.

Jason
But then we're back to clinical psychology.
So maybe the aversion to social-cog is that they mainly provide framework evidence (rather than diagnostic).

rabbitsnore
Let's take a different example, though... If we imagine a large-scale fraud case involving complex financial transactions, it's easy to imagine an expert being called just to explain how certain financial processes work because that knowledge is beyond the ken of the jury.
In the same way, much of psychology is outside of the common knowledge of a jury.

Jason
That's a good example and I think that's right. I may use that one the next time I am defending psychological science to lawyers!

rabbitsnore
Use it with my blessing!

Jason
#rabbitsnoreblessed

Will Crozier 🐙
So we know that a psychologist wouldn't be able to say "This is what happened" e.g., a confession expert saying "this confession is coerced"

Could a...bank expert I guess? opine as to the legality or illegality of certain transactions?

rabbitsnore
I don't think they're supposed to.

Jason
It's not an absolute rule in most places, but typically judges don't like it when experts opine on the ultimate issue, which I think Timothy mentioned above. Generally, the jury (or trial judge sitting as factfinder) is supposed to be the one who makes this call and the expert is not supposed to usurp that role.

And generally illegality is a legal thing.

rabbitsnore
I doubt a judge would take kindly to a finance expert being like, "Yeah, this was totally insider trading," on the stand.

Jason
Besides undervaluing it, as we discussed, I think they may overvalue it at times. For instance, I think they may think neuroscience is more rigorous and precise than it is – I read one case in which the trial judge described it as “objective” – we know that’s not true. It’s a subjective interpretation of a brain scan, in many cases.

rabbitsnore
It's interesting that a lot of the misconcenptions by the legal system we've brought up also apply to the general public -- who also seem to overvalue neuroscience.

Jason
It may be because judges don't usually have that much scientific training.

rabbitsnore
That's what I was thinking. Legal professionals don't have that sort of training, so they're probably relying on largely the same body of knowledge as laypeople, which is often going to be stereotypes, media portrayals, and whatnot.

Will Crozier 🐙
Asking judges and attorneys where they know what they know about science would be an interesting study!

Jason
I bet someone has done it!

Will Crozier 🐙
So it seems like we can agree that the courts and psychologists don't always see eye to eye on psychological science....and that can be due to misconceptions on both sides

Timothy, what psychology research do you think would benefit the courts?

rabbitsnore
Broadly speaking, I think the courts could benefit from research with specific relevance to legal standards that make empirically testable assumptions. For example, our friend (and prior chat guest) Fabi Alceste has done research related to the notion of custody – which is a legal concept that is probably far more complex than most people think. US case law suggests that a person is in custody if a reasonable person in the situation would feel as if their freedom of action was constrained in a manner tantamount to arrest. A basic question to ask in this context is, under what conditions do people feel restrained such that they can’t leave? That’s a question that can be studied scientifically.

There are lots of legal concepts and standards that might be worth studying with empirical methods. But an interesting concept that comes to mind (and this might strike people as an odd one) is the idea of “dignity.”

This is a concept US Supreme Court Justice Anthony Kennedy is fond of appealing to in his opinions, not least of which is his opinion in Obergefell v. Hodges10 – the decision that effectively legalized same-sex marriage in the US. Laws may be unconstitutional, the might argument go, if they deprive people of dignity. During his Senate confirmation hearing, Kennedy included in a description of what he considered violations of dignity, “the inability of the person to manifest his or her own personality, the inability of a person to obtain his or her own self-fulfillment.” Interestingly, he asserted that finding dignity and violations thereof was not subjective: “The task of the judge is to find objective referents for each of these categories.”

Objective reference is exactly the kind of thing science strives to provide. Maybe we should try to do so, insofar as it would assist the law and the process of justice.

Jason
Interestingly, Supreme Court justices are the least democratically appointed branch and so their views on what constitutes dignity, it could be argued, are the least representative of the general public.

Will Crozier 🐙
Maybe that's why they could use some help

rabbitsnore
I'm not arguing so much that the idea of dignity is a sound one any more than the idea of custody or the idea of voluntariness (as it relates to confessions). Rather, as long as the legal system is using ideas like that, we can (and maybe should) provide empirical evidence that bears on them.

Jason
I agree there is lots of research to be done and a lot of low-hanging fruit out there!

Will Crozier 🐙
Any specific ideas that would be particularly helpful, Jason? Low hanging fruit or otherwise?

Jason
Well I think Timothy has the right idea. Many legal rules advert to the notion of what is objectively reasonable and then the judge just tells us what that is! But that might better be solved by research that is more representative of the public (i.e., rather than what's reasonable to an often white person of high socioeconomic status)!

Will Crozier 🐙
So psych research with more diversity in sampling - rather than college kids?

rabbitsnore
Or in some cases, purposive sampling might be useful. That is, specifically targeting underrepresented groups or people who are the very subject of the case. Brown v. Board of Education9 comes to mind -- in which social scientists provided evidence that bore on the "separate but equal" doctrine.

Jason
I think copyright law is pretty good about this - they sometimes admit social scientific research getting at whether folks would likely confuse the product with another brand. Brown would be an example of what Monahan and Walker call legislative fact.

Will Crozier 🐙
Haha, I had never thought of copyright law as a sanctuary for social science research

rabbitsnore
I don't know of specific cases offhand, but I think the psycholinguistic research on pragmatic implication has been used in advertising disputes. Pragmatic implication occurs when people "read between the lines" of what is said to understand what something means (e.g., "It would be great if you could come to my party." = "You are invited to the party."). I think this research has been presented when advertisers have been sued for allegedly deceptive ads.

Jason
Yes and I think that makes perfect sense!

Will Crozier 🐙
That about wraps up my questions for you guys. Jason, any closing comments?

Jason
Thanks, Will and Timothy. I'd just reiterate what I said above. Ideas about how people think, feel and behave are embedded in most legal rules. So, the more cross-talk between the fields, the better!

rabbitsnore
Agreed.

Will Crozier 🐙
Well, recommend our blog to your lawyer friends and perhaps we can add a bit more of that to the world! haha

Jason
Will do!

Will Crozier 🐙
(More shameless self promotion)

rabbitsnore
...also if anyone needs a confession expert.

Jason
Is this the plugs section? Where you ask for plugs?

Will Crozier 🐙
Apparently it is - anything you want to plug? haha

Jason
Like and rate me on iTunes.

Will Crozier 🐙
Well, it's been a pleasure having you on Jason - thanks for stopping by and sharing your thoughts

Jason
Thanks and great job with the website!

rabbitsnore
Much appreciated!

Jason
Let's do some studies together soon!

Will Crozier 🐙
Calls for collaboration - always a great way to end a chat!

Follow Jason Chin on Twitter: @socpsychupdate

Notes

*The fundamental attribution error refers to the tendency for people to underestimate how much the situation influences others' behavior. For example, if you see someone driving over the speed limit and swerving through traffic, you may immediately think that the driver is a reckless person, rather than thinking that the driver is responding to an emergency.

**Legislative facts are broad, general facts that are relevant to the case at hand, but not specifically to the case at hand. Adjudicative facts are facts that are disputed by the parties in a specific case – such as the who, what, when, where, why, and how of the events involved in a case. Psychology could be applied to both. For example, whether schizophrenia can cause people, in general to react violently, is a legislative fact. Whether a specific defendant had schizophrenia, and reacted violently because of that schizophrenia, is an adjudicative fact.

*** The Dunning-Kruger Effect is a cognitive bias that describes the propensity for people who know very little about a topic to mistakenly believe they know a lot about that topic.

**** Haidt has argued that many moral arguments are after-the-fact justifications for the way we feel. That is, when we are morally offended (for example, by a heinous crime), we generally feel that it was wrong and then only afterward try to provide reasons that it was wrong.

References

[1] Kassin, S. M., Redlich, A. D., Alceste, F., & Luke, T. J. (2018). On the general acceptance of confessions research: Opinions of the scientific community. American Psychologist, 73, 63-80.

[2] Davis, K. C. (1942). An approach to problems of evidence in the administrative process. Harvard Law Review, 55, 364-425.

[3] Monahan, J., & Walker, L. (1994). University casebook series. Social science in law: Cases and materials (3rd ed.). Westbury, NY, US: Foundation Press.

[4] Walker, L., & Monahan, J. (1988). Social facts: Scientific methodology as legal precedent. California Law Review, 877-896.

[5] Shen, F. X., & Jones, O. D. (2010). Brain scans as evidence: truths, proofs, lies, and lessons. Mercer Law Review, 62, 861.

[6] Ambady, N., & Rosenthal, R. (1992). Thin slices of expressive behavior as predictors of interpersonal consequences. Psychological Bulletin, 111, 256-274.

[7] Bond Jr, C. F., & DePaulo, B. M. (2006). Accuracy of deception judgments. Personality and Social Psychology Review, 10, 214-234.

[8] R v. Mohan, 1976 Q.B. 1, 1976 Q.B.1 1 (1976).

[9] R. v. McIntosh, 1995 S.C.R.1 686 (1995).

[10] Obergefell v. Hodges, 135 S. Ct. 2071, 576 U.S., 191 L. Ed. 2d 953 (2015).

[11] Brown v. Board of Education, 347 U.S. 483, 74 S. Ct. 686, 98 L. Ed. 873 (1954).

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