"The best predictor of future behavior is …

… past behavior."


Past as prelude. So neat, so clean. So full of certitude. Like a fortune cookie Confucianism. Something you might hear on CSI: Special Victims Unit. A maxim cited by pop psychologist "Dr. Phil" McGraw, in one of his many self-help books.

I'm sure you have heard the mantra. It's creeping into risk assessment reports and court testimony by forensic psychologists. Sometimes, it's augmented with incendiary metaphors: The subject is "a ticking time bomb"; he is "carrying a hand grenade and it's just a matter of when he pulls the pin."

One current case of mine involves a guy with a cluster of several violent offenses a few years ago, when he was in his 20s. He was using drugs back then, and hanging around with a bad crowd. Plus, he is chronically psychotic. Not a good combination.

But if you predict future violence based on a set of risk factors like his, you will be wrong more often than not. Only about four out of ten of those individuals judged to be at moderate to high risk of future violence go on to reoffend violently, according to research. The low base rates of violent recidivism will be working against you.

Birth of a legend

So where does this idea that "the best predictor of future behavior is past behavior" come from, and does it hold any water?

Perusing psychology texts, it appears that the principle has circulated for decades. But as it gained traction, some boiled it down into a simpler, one-size-fits-all mantra. So, for example, the 2003 Complete Idiot's Guide to Psychology claims as an established "psychological fact of life" that, "when it comes to human beings, the best predictor of future behavior is past behavior." Period. End of story.

But this is a gross oversimplification. Psychological scientists who study human behavior agree that past behavior is a useful marker for future behavior. But only under certain specific conditions:

1. High-frequency, habitual behaviors are more predictive than infrequent behaviors.
2. Predictions work best over short time intervals.
3. The anticipated situation must be essentially the same as the past situation that activated the behavior.
4. The behavior must not have been extinguished by corrective or negative feedback. 
5. The person must remain essentially unchanged.
6. The person must be fairly consistent in his or her behaviors.

Here, by way of illustration, is a typical study of the phenomenon, involving college students' class attendance habits:

In a semester-long course, researcher Icek Ajzen found that a student's attendance rate for the first eight sessions correlated 0.46 with his or her attendance rate for the second eight sessions. As you can see, all the conditions are in place: Class attendance is a habitual and routinized behavior, the prediction span is very short, and there is little likelihood of meaningful changes in either the situation or the person. Yet still, the correlation is far from perfect.

Other examples from the classic studies: Frequency of exercise during a given time period is a pretty good indicator of exercise habits in the near future. Ditto for cigarette smoking and drug use.

But over longer time periods, even high frequency, habitual behaviors may undergo dramatic change. A smoker or heavy drinker might successfully quit the habit. A chronic thief might land a decent job, start a family and settle down.

As this last example suggests, researchers have also determined that the situation plays a critical role in behavior. The situation is often more determinative than individual character traits. Personality theorist Walter Mischel - frequently cited in connection with the "best predictor" maxim - suggests that behavioral consistency is best described through if-then relationships between situations and behaviors, as in: "She does A when X, but B when Y." So, a person may engage in heavy drug use when in the company of drug-using peers, but may stop using when she gets a fulfilling job and moves to the suburbs, or when she is staying with her strict grandmother.

Forensic psychologists jump aboard

It’s one thing to find a simplistic maxim where one would expect to - in an "Idiot’s Guide" or on Dr. Phil. But it is troubling to see it incorporated in forensic contexts, where the stakes are much higher.

Confusion creeps in when a risk marker is mistaken for an inevitability. It is true that people with a history of violence have a higher likelihood of committing violence in the future than do people who habitually turn the other cheek. Risk is especially acute for those with very extensive histories of violence across a range of situations. But this does not mean that everyone who has committed past acts of violence will continue to aggress forever (any more than someone with no prior violence is guaranteed to remain peaceable forever).

It's like claiming to know that because your teenage neighbor had a fender bender (or two) when he was first learning to drive, he will definitely crash his car again. He is probably at a higher risk of another collision than is his middle-aged mother, with her clean driving record. But he may or may not crash again. There are many intervening variables - whether he learned from his mistakes, the frequency and locations and times of day of his future driving, his choice of companions, the actions of other drivers on the road, the weather conditions, and so on.

The maxim also conflates all types of violence, and all types of offenders. For example, with detected recidivism among sex offenders falling somewhere between a low of about 3 percent and a high of no more than 15 percent, it's pretty hard to argue past as prelude. And if we apply the mantra to murderers, as did "Dr. Death" in Texas, we will be even further off the mark. In California over the past two decades, about 1,000 people have been paroled from prison after serving time for first- or second-degree murder. Their recidivism rate for murder?

Precisely zero, according to Nancy Mullane's Life After Murder.

The best-predictor axiom ignores such base rates, which are essential to accurate prediction. If we know the base rate of the criminal behavior we are trying to predict - whether murder or sex offending or general violence - and we know the frequency with which a person has engaged in that behavior, we can use a mathematical formula called Bayes's theorem to calculate a rough likelihood of the behavior's reoccurrence. (I recommend Nate Silver's The Signal and the Noise for great examples of the applications of this theory across a range of contexts, from poker to climatology.)

The maxim also snubs its nose at the age-crime curve, perhaps the most universal finding of a century of criminology research. As they reach their mid-30s or so, criminal offenders begin to slow down. Some mature naturally, some go through successful mentorship or treatment programs, some settle down and have families, some form mellower friendships, some simply burn out. Whatever the reasons, as research by Shadd Maruna and Sampson and Laub drives home, desistance is a virtual inevitability for all but the most die-hard minority of offenders.

This is not to say that the maxim is entirely useless. It may work fairly well under certain limited circumstances, if all of the following hold true:

1. We are predicting over a relatively short time frame.
2. The individual has a high frequency of violence.
3. The violence occurs in a variety of situations.
4. The person is faced with the same or similar situations.
5. He or she has not been deterred by negative feedback.
6. He or she has not changed in any other significant way.

But given lengthier time frames of prediction, our subject and his circumstances both undergo inevitable and often unpredictable changes, and we lose fidelity.

A ticking time bomb fails to ignite

In the case of the report I was reading this week, the mantra was a complete bust. The guy got out of jail and did great. He voluntarily sought treatment and cooperated with all terms of his supervision. By the time I saw him, he was leading a life as peaceable as a newborn lamb's. In his spare time, he even volunteered to help the needy at his local church.

If the evaluator had heeded the literature on criminal desistance, she might have seen this coming. The fellow had reached the age at which desistance becomes more the rule than the exception. He no longer associated with his old criminal peers. Perhaps most importantly, he had stopped using the drugs that had exacerbated his psychosis.

The past-as-prelude mantra fits with today's dominant, dark view of offenders as a bundle of perpetual risk factors, ticking time bombs just waiting to explode.

What it doesn't fit so well with is reality. 

Aurora massacre: To speak or not to speak?

The blood on the movie theater floor was still tacky when mental health professionals began pontificating on the psychology of the mass murderer. Among the brashest self-promoters was a forensic psychologist who shamelessly asserted his preternatural ability to "look inside the mind" of the Aurora, Colorado massacre suspect.

Much of the psycho-punditry reads like it was pulled from a psychoanalytic fortune cookie:

• James Holmes is a "deeply disturbed" individual. 
• He may, or may not, be psychotic and delusional. 
• He harbors a lot of rage.

Such "armchair psychology" is a natural byproduct of the news media's frenetic competition for online traffic. To object is as pointless as it would have been to stand in the killer's way and shout "stop!" as he opened fire during the Batman movie.

But some are nonetheless voicing criticism, saying it is both misleading and irresponsible to speculate at this early stage about the accused's state of mind. Curtis Brainard of the venerated Columbia Journalism Review goes so far as to call it unethical, a violation of the so-called "Goldwater Rule" of 1973. That principle cautions psychiatrists not to offer a professional opinion without having conducted a psychiatric examination and "been granted proper authorization for such a statement."

While that ethics rule applies only to psychiatrists, the American Psychological Association has a very similar one. Section 9.01 cautions psychologists to "provide opinions of the psychological characteristics of individuals only after they have conducted an examination of the individuals adequate to support their statements or conclusions."

But it is in the gray area of interpreting these ethics rules that reasonable minds differ. Indisputably, we should not attempt to clinically diagnose Mr. Holmes absent a formal evaluation. But must professionals with expertise in the general patterns underlying mass killings stand silently on the sidelines, refraining from offering any collective wisdom to the public?

As a blogger who frequently comments on breaking news stories pertinent to forensic psychology, I have often grappled with this conundrum. When the UK Guardian asked me to write a commentary on Phillip Garrido, the kidnapper and rapist of Jaycee Dugard, I ultimately decided that providing general information about the forensic implications of the case was an appropriate public service that did not violate any ethics rules.

Consider this commentary by high-profile forensic psychiatrist Michael Welner on a Washington Post blog:

Mass shooting cases have the common motive of an attacker seeking immortality. Each of the attackers have different degrees of paranoia and resentment of the broader community. Some are so paranoid that they’re psychotic. Others are paranoid in a generally resentful way but have no significant psychiatric illness. But you have to hate everyone in order to kill anyone. The threshold that the mass shooter crosses is one in which he decides that his righteous indignation and entitlement to destroy is more important than the life of any random person that he might kill. This is why mass shooting are invariably, invariably carried out by people who have had high self esteem. They are people who had high expectations of themselves. It’s not at all surprising to hear about these crimes in people who either valued their own intelligence or their own career prospects at one time. They’re people who are unfailingly unable to form satisfying sexual attachments and their masculinity essentially gets replaced with their fascination for destruction.

Now, I don't always see eye to eye with Dr. Welner, author of the controversial "Depravity Scale." But the above perspective has the potential to contribute to informed discussion of the Aurora tragedy. It doesn't matter whether every single detail turns out to be a precise fit; the comments are general enough to enlighten without stepping over the line to claim an ability to see into Holmes's troubled soul.

One could even argue that we as professionals have an affirmative duty to help offset the inane speculation that pours in to fill any vacuum in the cutthroat world of daily journalism: Portrayals of Holmes as a "recluse" and a "loner" because he didn’t converse with his neighbors; assertions that he "didn’t seem like the type" to massacre a dozen people, because he appeared superficially "normal"; simplistic theories blaming the tragedy on violence in the media or the legality of gun ownership.

Our field is positioned to help the public separate the wheat from the chaff. We can discuss the complex admixture of entitlement, alienation and despair that contributes to these catastrophic explosions. Equally important, we can remind the public that such rampages are rare and unpredictable, and that knee-jerk, "memorial crime control" responses are unwarranted and potentially dangerous. We can urge restraint in jumping to conclusions absent the facts, lest we -- as journalist Dave Cullen, author of the book Columbine, warns in yesterday's New York Times -- contribute to harmful myth-making:  

Over the next several days, you will be hit with all sorts of evidence fragments suggesting one motive or another. Don’t believe any one detail. Mr. Holmes has already been described as a loner. Proceed with caution on that. Nearly every shooter gets tagged with that label, because the public is convinced that that’s the profile, and people barely acquainted with the gunman parrot it back to every journalist they encounter. The Secret Service report determined that it’s usually not true. Resist the temptation to extrapolate details prematurely into a whole…. The killer is rarely who he seems.

But we should also recognize the limitations of our discipline’s micro focus on the individual, and encourage the public to grapple with the larger issues raised by this cultural affliction of the late-20th and early 21st century. As I commented last year in regard to the media coverage of the Jared Loughner shooting rampage in Arizona, journalists need to train a macro lens on the cultural forces that lead disaffected middle-class men -- like canaries in a coal mine -- to periodically self-implode with rage. Disciplines such as sociology, anthropology and cultural studies have much to contribute to this much-needed analysis.

The irony of the Aurora case is hard to miss. An attack in a movie theater featuring The Dark Knight Rises, a movie in which a masked villain leads murderous rampages against unsuspecting citizens in public venues including a packed football stadium and the stock exchange.

As Salon film critic Andrew O'Hehir noted in an insightful essay entitled, "Does Batman Have Blood on his Hands?":

Whether or not Holmes had any particular interest in “The Dark Knight Rises,” he saw correctly that in our increasingly fragmented culture it was the biggest mass-culture story of the year and one of the biggest news stories of any kind. Shoot up a KenTaco Hut or a Dunkin’ Donuts, in standard suburban-nutjob fashion, and you get two or three days of news coverage, tops. Shoot up the premiere of a Batman movie, and you become a symbol and provoke a crisis of cultural soul-searching.

Bottom line: The larger error is not for informed professionals to respond -- cautiously, of course -- to media inquiries but, rather, for the public to settle for facile explanations, in which calling someone crazy or disturbed is mistaken for understanding what is going on. 

POSTSCRIPT: See media critic Gene Lyons's article, linking to this post, at the National Memo. 

Related blog posts: 

• Arizona rampage: Analyzing the analyzers
• Can school shootings be prevented? 

Special journal issue on psychology-law available for free!

A special issue of Current Directions in Psychological Science showcasing the latest psychological research applied to the legal system has received enormous interest. As a result, the editors and Sage Publications are making the full contents available free to the public through June 15, 2011. The articles cover a wide range of topics of interest to my readers, including competency, violence risk assessment, profiling, false confessions, eyewitness evidence, and jury decision making. You are encouraged to download these articles for later reading, and to freely share these links with colleagues. 

  FULL CONTENTS - CLICK ON BELOW LINKS TO DOWNLOAD  

Comment From the Editor
Randall W. Engle
 
Editor's Introduction: Special Issue on Psychology and Law
Ronald P. Fisher
 
Resolving the Offender "Profiling Equations" and the Emergence of an Investigative Psychology  
David V. Canter
 
Forensic Interviewing Aids: Do Props Help Children Answer Questions About Touching?
Debra Ann Poole, Maggie Bruck, and Margaret-Ellen Pipe
 
Interviewing Cooperative Witnesses
Ronald P. Fisher, Rebecca Milne, and Ray Bull
 
Current Issues and Advances in Misinformation Research
Steven J. Frenda, Rebecca M. Nichols, and Elizabeth F. Loftus
 
Eyewitness Identification
Neil Brewer and Gary L. Wells
 
Outsmarting the Liars: Toward a Cognitive Lie Detection Approach
Aldert Vrij, Pär Anders Granhag, Samantha Mann, and Sharon Leal
 
Suspect Interviews and False Confessions
Gisli H. Gudjonsson and John Pearse
 
Current Directions in Violence Risk Assessment
Jennifer L. Skeem and John Monahan
 
Future Directions in the Restoration of Competency to Stand Trial  
Patricia A. Zapf and Ronald Roesch
 
The Utility of Scientific Jury Selection: Still Murky After 30 Years
Joel D. Lieberman
 
Expert Psychological Testimony  
Brian L. Cutler and Margaret Bull Kovera
 
The Psychology of Trial Judging  
Neil Vidmar
 
Jury Decision Making: Implications For and From Psychology
Brian H. Bornstein and Edie Greene

Arizona rampage: Analyzing the analyzers

It's an endless loop tape, spinning us in a vortex of irrationality so all-encompassing it almost starts to seem normal.

After every high-profile crime, experts charge out of their corners with their pet solutions: Restrict high-capacity gun magazines. Increase mental health services. Revise school or workplace procedures.

Conservative media psychiatrist Sally Satel is even using the Arizona tragedy as a platform for laws requiring schools and businesses to report to authorities any student or employee who it "ejects or otherwise removes …. out of concern about behavior and dangerousness." Talk about a civil liberties nightmare!

Memorial crime control

Such opportunistic crime-control advocacy works best during moments of public crisis. When the hysteria reaches critical mass, politicians appease anxious constituencies through yet another feel-good law. Then, the latest crisis dies down and people get back to their normal lives. Watching Fox-TV, they remain blissfully shielded from the dark side of memorial crime control.

Rather than capturing the monsters of the public's imagination -- lunatic rampagers, sexual predators, and homicidal gangsters -- this inexorable web of draconian laws ends up ensnaring the most vulnerable, mainly young African American and Latino men from poor communities.

Do you recognize the name Rodrigo Caballero? Unlikely. He is just one tiny speck in a mass of captive and unknown dark bodies, a 16-year-old mentally ill California boy sentenced to 110 years in prison for attempted murder. Any cathartic efforts of memorial crime control are short-lived, while the costly and unanticipated social costs live on. Young Mr. Caballero isn't due out of prison until 2110, long after he and all of the rest of us will be dead.

No profile of would-be assassins

There will always be the next rare event to fuel this cycle of knee-jerk response, ostensibly aimed at protecting us from every remote contingency. Hindsight bias is a powerful heuristic that obscures an unfortunate truth: It is very hard to accurately predict -- much less prevent -- individual-level violence. As I wrote four years ago, after Cho Seung-Hui's deadly rampage at Virginia Tech:

Many people -- and especially many adolescent and young adult men -- are troubled. Many are severely depressed. Many express disturbing, violent fantasies. Fortunately, only a tiny fraction commit lethal acts against others. And unfortunately, those who do often do not stand out ahead of time.

This is what forensic psychologist Robert Fein found when he conducted a Secret Service study of all political assassins and would-be assassins in the United States over the past 60 years. Contrary to popular mythology, the assassins fit no singular "profile." They were neither monsters nor martyrs, Fein said:

The reality of American assassination is much more mundane, more banal, than assassinations depicted [in movies].

The myth of the deranged killer

Jared Loughner’s delusional ramblings, revealed to the world by intrepid Internet sleuths, are the only explanation some people need. But they are something of a red herring.

First, as advocates for the mentally ill are quick to point out, the link between psychosis and violence is far from settled. Most people with severe mental disorders do not become violent. Any increased risk is miniscule compared with the risk posed by use of alcohol or drugs, according to large-scale studies. As Vaughan Bell puts it in his lucid summary of this research:

Psychiatric diagnoses tell us next to nothing about someone's propensity or motive for violence…. It's likely that some of the people in your local bar are at greater risk of committing murder than your average person with mental illness.

But even when an assassin does harbor delusional beliefs, this is not sufficient explanation. Loughner's gender likely played a role, too, as men commit far more violence than women. Yet we would never think we had explained the Tucson rampage with the statement: "Loughner was a man."

In fact, the Secret Service study found that the assassins who were delusional -- about one-fourth of the total -- acted based on the same types of motivations as non-delusional assassins. As reporter Douglas Fox summarized:

Some hoped to achieve notoriety by killing a well-known person. Others wanted to end their pain by being killed by Secret Service. Still others hoped to avenge a perceived, idiosyncratic grievance unrelated to mainstream politics. Some hoped, unrealistically, to save the country or call attention to a cause. And some hoped to achieve a special relationship with the person they were killing.

Selecting one's lens: Micro or macro?

In our professional role, forensic psychologists use a micro lens, focusing on the individual level of analysis. But when commentators focus solely on individual-level factors, they divert the public from contextual factors that may be more amenable to prevention.

In other words, at the micro level there is no question that Loughner is a troubled young man. But at the macro level, his choice of targets certainly reflects the political tensions in the United States and especially in Arizona, which even the local sheriff described as a "Mecca for prejudice and bigotry."

Sarah Palin is able to evade responsibility for her violent rhetoric by strategically refocusing on the culturally entrenched myth of the dangerous schizophrenic, and calling Loughner "deranged" and "evil."

Ironically, it is the mentally unstable like Loughner who are most vulnerable to extremist rhetoric, and other memes floating around in our cultural ethos. As prominent forensic psychologist and law professor Charles Patrick Ewing noted:

These influential politicians and commentators who use violent rhetoric and images -- such as putting a member of Congress in the crosshairs, telling supporters that it is time to 'reload' and suggesting that voters unhappy with Congress resort to 'Second Amendment remedies' -- must realize that they have an incredibly wide audience. At least some members of that audience (both sane and insane) will view their inflammatory statements as an invitation to violence…. The blame for these killings does not lie with the perpetrator alone."

"Stochastic terrorism" is the term invoked by one professor of communications to describe this phenomenon, of "use of mass communications to stir up random lone wolves to carry out violent or terrorist acts that are statistically predictable but individually unpredictable."

What if Abdul had done it?

That the micro lens is a deliberate choice becomes clearer if we ask ourselves how media coverage might be different if a Muslim from the Middle East had shot U.S. Rep. Gabrielle Giffords. Would the focus still be on individual pathology? Or would it be on his political affiliations and the content of his rhetoric?

The din of rhetoric about mental illness drowns out the voices of those framing Loughner's attempted assassination as an act of political terrorism. People like Jesse Muhammed, Sahar Aziz, and Cenk Uygur, who asks incredulously:

Is this a joke? He shot a politician in the head. He called it an "assassination." What part of that was unclear? … [W]hy does the act have to be either psychotic or political? It's obviously both.… The conservative hate-mongers don't create psychos…. [But] they channel their fear, anger and paranoia…. They load them up with violent imagery, whether it's talk of cross-hairs or second amendment remedies or the tree of liberty being refreshed with blood. Then when they get a violent reaction they pretend to be surprised and outraged that anyone would suggest they were the least bit culpable. The reality is that it is a simple formula -- violent imagery in, violent results out.

In the final analysis, the causes of violence are multifaceted and difficult to disentangle. And it is impossible to predict which troubled, angry and alienated young man will engage in lethal violence. But one thing is certain: More laws are not the answer. They cast too wide a net, and distract from the search for deeper solutions.

Related blog posts:

Loughner update: Skirmishing over competency (March 22, 2011) 

Can school shootings be prevented? (April 19, 2007)
Systems failure or black swan? New frame needed to stop memorial crime control frenzy (Oct. 19, 2010)
Backlash growing against criminal profiling (Sept. 14, 2010)

No reliable method to determine pedophilia, study finds

http://www.psychologytoday.com/blog/witness/201011/no-reliable-method-determine-pedophilia-study-finds

Good news for sex deviants seeking jobs with TSA

Lest you think that TSA hiring agents can protect airline passengers from sexual groping by weeding out the deviant from the "normal," they cannot. There's no accurate way to know. My full report on a new study about diagnosing pedophilia, and how it relates to the viral TSA controversy, is online at Psychology Today.

The study is: "Pedophilia: An evaluation of diagnostic and risk prediction methods," by Robin J. Wilson, Jeffrey Abracen, Jan Looman, Janice Picheca, and Meaghan Ferguson, in Sexual Abuse: A Journal of Research & Treatment

And don't miss Jonathan Mann's new video, "I don't like the TSA"

Backlash growing against criminal profiling

UK Guardian: "Psychological profiling 'worse than useless' "

In the beginning, there was Malcolm Gladwell's 2007 masterpiece in the New Yorker, exposing criminal profiling as clever sleight of hand. Three years later, reports in both New Scientist and the Guardian of UK are expressing mounting concerns over the pseudoscientific technique made bigger than life in fictional TV shows.

Leading the backlash is psychology professor Craig Jackson of the Centre for Applied Criminology at Birmingham City University. He will critique the scientific validity of profiling at the British Science Festival this week. Not only is profiling unscientific, say Jackson and a growing chorus of others, but it risks bringing the field of psychology into disrepute. As Ian Sample reports in today's Guardian:

In many cases, offender profiles are so vague as to be meaningless, according to psychologist Craig Jackson. At best, they have little impact on murder investigations; at worst they risk misleading investigators and waste police time, he said.

"Behavioural profiling has never led to the direct apprehension of a serial killer, a murderer, or a spree killer, so it seems to have no real-world value," Jackson said.

Despite profiling's lack of demonstrated validity, police forces around the world bring in behavioral experts in complex or high-profile cases, often to appease victims' families or the media. In the UK, for example, The Home Office keeps a register of experts who are qualified to render offender profiles based on crime information, the Guardian reports.

"It is given too much credibility as a scientific discipline. This is a serious issue that psychologists and behavioural scientists need to address," [Jackson] said. "People believe psychologists like 'Cracker' can exist." In the 1990s television series, police apprehended criminals with help from an overweight, chain-smoking alcoholic psychologist.

Jackson quoted one behavioural scientist as saying he "climbs inside the minds of monsters" and "takes the expression frozen on the face of a murder victim and works backwards."

"They bring themselves forward as if they are shamans who are cursed by nightmares and picturing dead people," Jackson said.

Jackson argues that, since people from marginalized groups are the primary victims of murder, "if we really want to deliver on the objective of reducing the numbers of people who fall victim to violent crime, then we would be just as well concentrating on eradicating homophobia, prejudice against sex workers and the elderly, rather than 'delving' into the heads of serial killers."

In an interview published today in the London Evening-Standard, the vice-chair of the British Psychological Society's forensic psychology division distanced forensic psychologists from criminal profiling. Carol Ireland said forensic psychologists worked in a wide range of areas, including offender risk assessments and interventions, helping victims, and conducting research.

A critical report by Jackson and two colleagues, "Against the Medical-Psychological Tradition of Understanding Serial Killing by Studying the Killers," is slated for publication next month in the legal journal Amicus Curiae, published by the Institute of Advanced Legal Studies at the University of London.

Related news coverage:

• "Crime 'crackers' no better than witch doctors, says psychologist," London Evening-Standard, Sept. 14, 2010

Related blog resources:

• Of profiling, astrology, and magic : Malcolm Gladwell exposes the tricks of forensic profilers (Nov. 7, 2007)

• Criminal profiling strikes out again: British case also features missteps by police, prosecutors, tabloid media (Dec. 24, 2008)

• Pseudoscience in policing (Oct. 19, 2008)

• What's it take to become a forensic psychologist? Profilers. Silence of the Lambs. The criminal mind. So eerie, so glamorous. (Sept. 19, 2007)

• "The Tim Masters Case: Chasing Reid Meloy" (Feb. 2, 2008)

• Fascinating new twists in Tim Masters case : Expert witness psychologist cited FBI profiler who had rejected prosecution theory of case (Dec. 20, 2007)

• Report provides blueprint for reducing wrongful convictions (July 9, 2007)

What is a gang?

A group of violent thugs? A social club? Troubled, homeless losers who are "hard to love"?

And what is gang membership? Is it a fixed identity, or something fluid, which urban youngsters claim or don't claim according to external circumstances and the flow of their lives?

How can we explain why, even in the roughest neighborhoods, at most 10 percent of youths belong to street gangs? Who are the other nine out of ten, and how do they negotiate survival without affiliation?

For answers to these complex questions, and more, I recommend a new book from New York University Press, Who You Claim, written by John Jay College of Criminal Justice sociology professor Robert Garot based on ethnographic researcher at a continuation school in Southern Calfornia.

Garot's nuanced analysis is a refreshing antidote to the kind of simplistic categorization that we see in corrections and in forensic practice, where young people being processed through the system are treated as if the label of gang member explains everything that we need to know about them.

His bottom-line message: Beware reifying gangs as fixed and essential components of identity, when even their members do not see them as such. As urban centers create increasingly fluid possibilities for identity -- exemplified by Polish-Brazilian and Mexican-Korean cuisines -- identity is becoming much more malleable and flexible than such a narrow and pejorative focus would lead us to believe.

My complete review, at Amazon, is HERE.

On police, profiling, and Henry Gates

Guest essay by Sam Sommers*

When it comes to matters of race, the problem with asking how much progress we've made is not that there isn't a right answer. It's that there are two. Ask White Americans about race relations, and most focus on how far we've come. Ask Black Americans, and you're more likely to hear how far we still have to go.

Have we made strides when it comes to racial profiling? Sure. The practice now has a well-known name, jurisdictions keep statistics to track it, and commissions have been established to eradicate it. But what the arrest of Dr. Gates crystallizes is that we still have a ways to go. Whether the neighbor who called police or the officer who arrived on the scene consciously considered race is beside the point. What we know from scores of studies is that race influences our mental calculus -- sometimes when we aren't aware of it, when we don't want it to, and even on the police force.

In psychological research, participants exposed to subliminal photos of Black men are quicker to identify ambiguous images as weapons. Respondents in police simulation studies -- including actual officers -- are more likely to mistake innocuous items for guns when held by a Black man. These are basic human tendencies to which many of us fall victim, yet they aren't inevitable with proper vigilance or training.

That's what makes knee-jerk denials that race played a role in Gates' arrest so disappointing. I'm not arguing that race was the only reason things went down as they did. I wasn't there; details remain fuzzy. But let's be honest: White Harvard professors just don't get charged with disorderly conduct in their own homes. And when Black men of less renown are arrested under similar circumstances, we don't hear about it on the news.

Sure, it's dangerous to read too much into the anonymous comments of web users and the incendiary efforts of bloggers who seek to draw attention (and web traffic) to themselves. But to me, one of the most striking aspects of this story is how angry some White people seem to be in response to it, as if the mere suggestion that race had anything to do with Gates' arrest is a) ridiculous, b) offensive, and c) an indcitment of the American way of life. Check out, for example, some of the initial reader responses to the on-line story of the arrest in my hometown Boston Globe.

I've said it before, and I'll say it again: there are few things White Americans find more aversive than talking about race. But to dismiss out of hand the relevance of race to Gates' arrest flies in the face of empirical data, not to mention good, old-fashioned, common sense. You don't have to be an expert to understand that things like this just don't happen to White professors at Harvard.

*From the New York Times, posted with the written permission of Sam Sommers. For the entire Times on-line forum, featuring invited essays by seven leading experts, click HERE. Sommers has also written a further update on the case, More Gates Fallout, at his informative blog, Science Of Small Talk.

Sommers is an award-winning social psychologist at Tufts University in Massachusetts who has testified in murder trials as an expert witness on racial bias. My prior posts about his work include:

• Racial bias in jury selection is common yet denied, study finds

• Colorful juries more competent

Will “revolutionary” Diana Screen end pedophile menace?

Vatican enlisting psychologists to perform miracles

The new movie Doubt paints the issue of pedophilic priests in shades of gray. Is the priest (played by Philip Seymour Hoffman) really a pedophile? Or is the head nun (Meryl Streep) just after him because, with his friendly manner and long fingernails, he fits her stereotype? Most provocative of all is the ostracized boy's mother (Viola Davis), who cares more about the priest's kindness to her son than about whether the relationship is sexual.

The movie is set in the 1960s, two decades before the pedophilia scandals sprang into the limelight to tarnish the reputation of the Catholic Church. Revelations of sexual misconduct by priests resulted in staggering financial losses - an estimated $2 billion in civil damages paid by the U.S. Catholic Church alone.

Anxious to mend its reputation and plug the money drain, the Vatican just announced a new fix: Candidates for the priesthood will undergo psychological screening to determine their suitability for the job.

What makes a candidate unsuitable, according to the Vatican? "Uncertain sexual identity," "deep-seated homosexual tendencies," and "grave immaturity" are among the factors. Painting a pseudoscientific veneer on the campaign, the Vatican said "expert" psychologists will screen select candidates on a case-by-case basis.

Mental health professionals, already flush with domain expansion into the emergent sex offender industry, are rushing into this new and potentially lucrative niche.

Leading the charge is Gene Abel, the psychiatrist who invented the controversial Abel Screen, which measures sexual proclivities based on how long men look at visual images of different types of models. Abel is promoting a new "pass/fail" test called the Diana Screen as a "breakthrough in technology" that can accurately identify men who have molested children.

"Who should use it?" asks the tool's website. "Any organization where there are professionals or volunteers who work with children," including churches, youth groups, schools, hospitals, foster care homes, and amusement parks.

In an appeal that combines sex panic emotionalism with a promise of revenue, Abel asks professionals to step forward and "make a difference" by becoming Diana Screen administrators: "You don't just add to your business opportunity, you take a stand against molestation and you help others to also take a stand."

Who can resist an appeal like that?

A quick web search found several psychologists already offering to do Diana Screens for employers. One bragged of having a "Certificate of Achievement" from Abel "in recognition of [his] knowledge about this important technology."

Child molesters are a heterogeneous bunch, with no unitary psychological "profile." So, before rushing to sign on, I decided to read the published literature on the Diana Screen to find out how it works, and whether it is reliable and valid.

Searching "Diana Screen" in an academic database, I did not get any hits. An Internet search was slightly more productive. I found several presentations by Abel. He presented the Diana Screen to the Society for Sex Therapy and Research; the Assessment, Treatment and Safe Management of Sexually Abusing Children, Adolescents, and Adults conference, and the California Coalition on Sexual Offending (CCOSO).

At these conferences, Abel reported on research he conducted with 100-plus applicants for priesthood training jobs. Unfortunately, the research does not appear to have been peer-reviewed or published, as required for admissibility in court under the Daubert standard.

Searching further, I found some strategically placed advertising; searches with the keywords "child molestation" cause Diana Screen ads to pop up on some news sites. The Screen was also a featured exhibitor at this year's conference of the Chartered Property Casualty Underwriters Society, which offers "cutting-edge tools" for "risk management professionals."

More humorously, in the blogosphere I bumped into a group of sex offenders discussing how easy it is to beat the test (and its precursor, the Abel). All you have to do, wrote one man, is ignore the instructions to rate your sexual arousal level to each slide, and instead respond at "a regular timing interval," which is what is really being measured. [PS: The link to their conversation went dead after this post was published.]

"You'll laugh when you find out just how easily the test can be beaten! The entire thing rides on the theory that no one will know what it's really testing."

Another agreed: "It's so seriously EASY to play the test like a harp."

These sex offenders would likely quarrel with the Screen developers' claim that it can identify "over 50 percent of actual child sexual abusers."

But my own question about the 50 percent success rate was, How can they know they are identifying half of all pedophiles? And, perhaps more importantly from an ethical point of view, what is the rate of false positives, or people whom the test wrongly identify as child molesters?

Hoping to learn more, I contact the company directly and asked for any published research. In due time, I received a packet of materials - glossy brochures and fliers, a sample report, graphs, and more promises that the Screen will help "bring an end to child molestation." No references to published research, though.

The materials did include a handout on the aforementioned (unpublished?) study of candidates for religious ordination. Of the 135 applicants screened, 18 (or about 13 percent) failed the test. Of those, 7 "were found to be true sexual risks to children" (based on followup inquiry and polygraph testing), while 2 "were found to have mental health problems" and 9 "required a closer look, but were found to have little or no risk."

Stated another way, that's a false positive rate of at least 50 percent. Even if it is just a screening test, psychologists should be cautious in administering a test with such a high false-positive rate and no published, peer-reviewed data on its reliability or validity.

More fundamentally, this type of testing raises philosophical issues about how far society should go in the name of protecting children, especially when most victimization is done not by teachers or amusement park workers but by family members. Who, for example, should be screened? As a colleague commented, it is one thing to screen airline pilots for alcohol abuse, but if priests, teachers, hospital employees, and even carnival workers will be screened, where will we draw the line? How much personal information are employers entitled to know? And what recourse will there be for those who are denied employment or lose their jobs based on their innermost thoughts, their sexual identity, an incident in their distant pasts, or - worst of all - erroneous test results?

The most pernicious problem with false positives is, how can one really know? As the movie Doubt suggests, proving innocence is difficult, and those who claim to be protecting children may have more complicated motives.

* * * * *

JULY 2015 POSTSCRIPT: The Atlantic has just published an interesting article on the controversies swirling around Abel Assessment by Maurice Chammah, a staff writer at The Marshall Project.

Criminal profiling strikes out again

British case also features missteps by police, prosecutors, tabloid media

In death, Rachel Nickell became an icon of the sexual brutalization of women. The London model was just 23 in July of 1992, when she was strolling across Wimbledon Common with her 2-year-old son and was stabbed 49 times, sexually abused, and almost decapitated in a frenzied, daylight attack.

As pressured mounted to solve the horrific murder and several other similar crimes, detectives turned to Paul Britton, a forensic psychologist with near-mythic stature in the field of criminal profiling.

Britton was suspicious of Colin Stagg, a lonely dog lover who had popped up on police radar when he replied to an ad in a lonely hearts magazine. With Britton’s help, police set a trap. They had a policewoman, "Lizzie James," befriend Stagg. Lizzie tried but failed to get Stagg to admit to killing Nickell. A judge threw out the case based on the illegality of the sting operation, but Stagg became Britain’s premiere pariah, villainized by the tabloid press as a black magic practitioner who had "gotten away with murder."

Britton, meanwhile, used the case to bolster his professional reputation, and featured it in his boastful 1998 autobiography, "The Jigsaw Man."

But Britton had made a catastrophic blunder. In pursuing his pet theory, he failed to connect the killing of Nickells and another young woman either to each other or to the "Green Chain rapes," a series of similar, frenzied, random knife attacks on women in the time period leading up Nickell's murder.

As forensic psychology professor Laurence Alison pointed out, "Frenzied random motiveless knife attacks on women are rare. Even more unusual are frenzied, random knife attacks on women with their young children present. Here was Britton with two of them under his nose and no one noticed."

Years later, the high-profile case came to a close when a paranoid schizophrenic named Robert Napper was tied to the killing by DNA evidence. Last week, Napper pleaded diminished responsibility due to mental illness and was sentenced to an indefinite term in a high-security hospital. He is suspected in at least 106 crimes involving 86 women.

Critics say that Nickell and other women would have been saved if police and prosecutors had followed all leads rather than blindly pursuing an innocent man. Napper came onto police radar screens at least eight times dating back to 1989. Some tipsters specifically linked him to the sexual assaults; beat cops in one incident described him in their notes as "strange, abnormal, should be considered as a possible rapist," and his own mother turned him in for rape. Astonishingly, police still did not pursue him for Nickell's murder even after DNA tests in 1994 tied him to the Green Chain rapes in 1994.

The case features the same type of investigative tunnel vision and prosecutorial stubborness we saw in the Norfolk Four case (see my blog post here) as well as the dangers of reliance on alluring but pseudoscientific techniques such as criminal profiling.

As one commentator put it, "Britton would never have impressed detectives if he had said that Stagg was a bit of a weirdo. When he dressed up that same thought in psychological language and talked of 'deviant interests' and 'sexual dysfunctions,' he sounded fatally convincing."

After his acquittal, Stagg filed a misconduct complaint against Britton with the British Psychological Society, but the case was dismissed in 2002, two years before the DNA evidence conclusively proved Stagg's innocence.

Photos (from top): Rachel Nickell (murder victim), Paul Britton (profiler), Colin Stagg (innocent man), Robert Napper (serial killer).

Laurence Alison, chair of forensic psychology at Liverpool University, has a new book on the Napper case, Killer in the Shadows. Journalist Ted Hynds co-authored Stagg's account, Pariah. The Guardian of London has full coverage of the Nickells case. My previous articles on criminal profiling are here.

Pseudoscience in policing

The October issue of Criminal Justice and Behavior is a special issue on Pseudoscientific Policing Practices and Beliefs. There are some great articles and, best of all, Sage is offering free access to those of you without access to academic databases through the end of this month.

As those of you who have been reading my blog for a while know, criminal profiling is one of my pet peeves (See last year's post, "Of profiling, astrology, and magic.") So, my favorite article in the current issue is "The Criminal Profiling Illusion: What's Behind the Smoke and Mirrors?"

The idea that police can deduce a suspect's characteristics from the crime scene has no strong empirical support and may indeed be an illusion, say the authors, Brent Snook, Richard M. Cullen, Craig Bennell, Paul J. Taylor, and Paul Gendreau, who go on to argue that the technique should not be used as an investigative tool:

There is a belief that criminal profilers can predict a criminal's characteristics from crime scene evidence. In this article, the authors argue that this belief may be an illusion and explain how people may have been misled into believing that criminal profiling (CP) works despite no sound theoretical grounding and no strong empirical support for this possibility. Potentially responsible for this illusory belief is the information that people acquire about CP, which is heavily influenced by anecdotes, repetition of the message that profiling works, the expert profiler label, and a disproportionate emphasis on correct predictions. Also potentially responsible are aspects of information processing such as reasoning errors, creating meaning out of ambiguous information, imitating good ideas, and inferring fact from fiction. The authors conclude that CP should not be used as an investigative tool because it lacks scientific support.

There's quite a lineup of scholarly experts behind the other articles in the special issue, too:

• Introduction to the Special Issue: Pseudoscientific Policing Practices and Beliefs by Brent Snook

• Science and Pseudoscience in Law Enforcement: A User-Friendly Primer by Scott O. Lilienfeld and Kristin Landfield

• Reducing Misconceptions and False Beliefs in Police and Criminal Psychology by Michael G. Aamodt

• Logic and Research Versus Intuition and Past Practice as Guides to Gathering and Evaluating Eyewitness Evidence by John Turtle and Stephen C. Want

• Hypnosis and the Law: Examining the Stereotypes by Graham F. Wagstaff

• Effective Policing: Understanding How Polygraph Tests Work and Are Used by William G. Iacono

• Confession Evidence: Commonsense Myths and Misconceptions by Saul M. Kassin

• Nonverbal Dominance Versus Verbal Accuracy in Lie Detection: A Plea to Change Police Practice by Aldert Vrij

• Apprehended Without Warrant: Issues of Evidentiary Warrant for Critical Incident Services and Related Trauma Interventions in a Federal Law Enforcement Agency by Katherine M. Newbold, Jeffrey M. Lohr, and Richard Gist

• Commentary: Sense, Common Sense, and Nonsense by David C. Flagel and Paul Gendreau

Check it all out here.

Photo credit: Troy & Patrice