Showing posts with label CSI effect. Show all posts
Showing posts with label CSI effect. Show all posts

August 2, 2013

New analyses undermine perception of DNA infallibility

Rags-against-riches case highlights technology's pitfalls

If you trust in the technology of DNA matching, it was an impeccable case:

Lukis Anderson's DNA matched that found on the fingernails of a San Francisco Bay Area millionaire killed in a home-invasion robbery. Based on the match to Anderson’s sample in the DNA database, the homeless man was arrested on a potential capital murder charge and spent five months in jail.

Fortunately for him, Anderson had an airtight alibi: He was lying in a hospital bed miles away, drunk to the point of unconsciousness. He also had no known connection to Raveesh "Ravi" Kumra, a cell phone entrepreneur and former winery owner who was killed during a home-invasion robbery near San Jose, California.

Although Anderson's attorneys initially thought there might have been a mix-up at the crime lab – the most common cause of erroneous DNA matches – an investigation ruled out improprieties. This despite the fact that, in an ironic twist, the technician who handled the DNA evidence in the case was previously implicated in a crime lab scandal in nearby San Francisco.

Prosecutors think they have solved the mystery: The paramedics who responded to Kumra’s home were the same two who had brought Anderson to the hospital via ambulance about two hours before the home-invasion attack on Kumra began. They likely inadvertently transferred Anderson’s DNA to Kumra via their equipment or clothing.

The local prosecutor called the case unique. But this is far from the first time that cross-contamination has led to a wrongful DNA match.

One of the strangest, most infamous and most embarrassing cases was the "Phantom of Heilbronn." A mystery woman was linked to six murders and dozens of other crimes across Germany and Austria through DNA found on everything from a heroin syringe to a cookie to a stolen car. Desperate police turned to profilers, a monetary reward and even fortune-tellers and psychics to no avail. Finally, after 15 years, the case was cracked: Evidence collection kits had accidentally been contaminated by a worker at a cotton swab factory. Forensic swabs are sterilized, but sterilization does not kill DNA.

In Australia, meanwhile, a 20-year-old man named Farah Jama was convicted and spent time in prison for a rape that likely never even took place. The same forensic officer had collected his DNA in an unrelated matter a day before collecting DNA from a woman who was found unconscious at a Melbourne nightclub. The woman had no recall of events and never claimed she was assaulted; nonetheless, Jama -- who didn’t know the woman and denied ever setting foot inside the nightclub -- spent 15 months in prison before his conviction was overturned.

Potential contamination of DNA evidence also factored into the reversal of Amanda Knox’s conviction in the odd Italian case that received international scrutiny. (Stay tuned on that convoluted case, by the way; the acquittal has now been overturned and a retrial in abstentia is scheduled to begin next month.)

The fact that an airtight alibi did not prevent Alexander from languishing in jail for five months, with a potential death sentence hanging over his head, highlights the problem of blind faith in the reliability of DNA evidence. As Osagie K. Obasogie, a law professor at Hastings School of Law in San Francisco and a senior fellow at the Center for Genetics and Society, argues in a compelling New York Times op-ed:
[T]he certainty with which prosecutors charged Mr. Anderson with murder highlights the very real injustices that can occur when we place too much faith in DNA forensic technologies. In the end, Mr. Anderson was lucky. His alibi was rock solid; prosecutors were forced to concede that there must have been some other explanation. It’s hard to believe that, out of the growing number of convictions based largely or exclusively on DNA evidence, there haven’t been any similar mistakes.
Chance matches more common than thought

But there may be bigger and more ominous problem than the rare transfer errors. The claim that random DNA matches are just about impossible, promoted by crime shows like CSI and powerfully influential in court, turns out to be flat-out wrong. As DNA databases become more and more massive, so too do the odds of chance hits.

An audit of Arizona’s 65,000-profile DNA database turned up almost 150 matching pairs, collected from different people. The California case of John Puckett is frequently cited as an example of misleading over-claiming about the reliability of DNA matches. Puckett is serving life due to a cold hit in a 1972 killing. Jurors heard testimony that there was only a one-in-a-million chance of a coincidental match. But, as Obasogie points out, that figure is misleading, according to an analysis by the National Research Council:
It reflects the chance of a coincidental match in relation to the size of the general population (assuming that the suspect is the only one examined and is not related to the real culprit). Instead of the general population, we should be looking at only the number of profiles in the DNA database. Taking the size of the database into account in Mr. Puckett’s case (and, again, assuming the real culprit’s profile is not in the database) would have led to a dramatic change in the estimate, to one in three.

This overdue recognition of the fallibility of DNA technology is causing some to call for greater oversight and to rethink the idea of allowing convictions based solely upon cold hits from DNA evidence.

Obasogie's final warning is profound:
For far too long, we have allowed the myth of DNA infallibility to chip away at our skepticism of government’s prosecutorial power, undoubtedly leading to untold injustices. In the Anderson case, thankfully, prosecutors acknowledged the obvious: their suspect could not have been in two places at once. But he was dangerously close to being on his way to death row because of that speck of DNA. That one piece of evidence -- obtained from a technology with known limitations, and susceptible to human error and prosecutorial misuse -- might mistakenly lead to execution at the hands of the state should send chills down every one of our spines. The next Lukis Anderson could be you. Better hope your alibi is as well documented as his.

Related blog post: DNA science on trial (April 17, 2009)

Blogger note: As always, it was great meeting blog subscribers during my seminar and training tour at Bond University in Queensland and the American Psychological Association convention in Honolulu. Thanks to all of you who attended and participated. The trainings were great fun; now it's back to the old grindstone as I head home and get back to work.

September 30, 2012

The taint of a false confession

Ripple effects bias parties, contaminate "independent" evidence 

Michael Crowe, age 14, falsely confessing to murdering his sister
With the recent tidal wave of scholarly research into false confessions, informed forensic psychologists are by now tuned in to the phenomenon. We know, for example, that they played a role in one out of four DNA exoneration cases. We are aware of their compelling nature, and can cite examples such as the Central Park Jogger case in which they produced profound miscarriages of justice.

But let's take it one step further. What if, once police elicit a false confession from a suspect, it contaminates everything and everyone in touches -- from the prosecutor, the judge, and even the suspect's own attorney all the way to the fingerprint identification and even, perhaps, the DNA match?

That is the troubling thesis raised by Saul Kassin, a pioneer in the psychological study of false confessions, in an article in the current issue of the American Psychologist.
  
"Corroboration inflation"

Research shows us that such a contaminating effect is plausible. For example:
  • Fingerprint experts who were told the suspect had confessed were more likely to change their opinion and make an incorrect match, as compared with experts who were told the suspect was already in custody at the time of the crime. (1)
  • Polygraph examiners were significantly more likely to opine that an inconclusive chart showed deception when they were told the suspect had confessed. (2)
Bizarre case of multiple false confessions and prosecutions
Such findings may extend to other forensic science that requires subjective judgments, Kassin argues, including comparative analyses of ballistics, hair and fiber, shoeprints, tire tracks, handwriting and even DNA. Although CSI-style TV shows portray such evidence as infallible, a 2009 study by the National Academy of Sciences found widespread errors and bias in the collection and analysis of evidence.

That's not to mention egregious cases of intentional fraud in forensic laboratories that pop up with alarming regularity, such as a case in Boston, Massachusetts currently garnering headlines. There, a lab worker with allegedly bogus credentials as a chemist intentionally fabricated positive drug test results. Over a 9-year period, Annie Dookhan tested an estimated 60,000 drug samples confiscated from about 34,000 criminal defendants. Dookhan reportedly admitted writing reports listing samples as positive for illicit drugs even though she had never tested them; sometimes, "if a sample tested negative, she would take known cocaine from another sample and add it to the negative sample to make it test positive for cocaine," according to the Huffington Post's account. Dookhan has been arrested and the lab is temporarily shuttered.

Kassin points to an archival study conducted by he and two colleagues which found that, in DNA exoneration cases, false confessions were often accompanied by other errors, including improper forensic science, mistaken eyewitness identifications and/or the testimony of dishonest informants. Importantly, the confession preceded the other case errors in two-thirds of cases, suggesting it may have had a corrupting influence.

Such findings suggest that the legal system's longstanding assumption that independent sources of evidence provide confirmation of a suspect’s guilt may be wrong. Rather, Kassin writes, "confessions can spawn other incriminating evidence, creating an illusion of corroboration":
Amanda Knox, wrongly convicted in Italy
"Supported by 100-plus years of basic psychology and the research reviewed herein, confession-induced corroboration inflation challenges a core premise in law. Both pretrial corroboration requirements and a harmless error analysis on appeal rest on the assumption that the corroborating evidence on record is nonredundant and independent of the confession. It now appears that this assumption is often incorrect, that the other evidence may be tainted by confession, and that the appearances of corroboration at pretrial and the sufficiency of evidence on appeal may be more illusory than real."
"Hollywood productions"

Especially pernicious is the frequent situation in which police -- either intentionally or inadvertently -- feed an innocent suspect information that only a guilty party should know. Taking on the aura of a carefully scripted movie production with the confession as the central plot device, the confession is carefully drawn out of the suspect over hours and even days until in its final version it includes vivid details and plausible motivations.

Such an account proves virtually impossible for a judge or a jury to discount. The scripted confession thus becomes the be-all, end-all of the case, contaminating the minds of all who are exposed to it:
  • POLICE close the investigation, deem the case solved, and overlook exculpatory information, even when (as Richard Leo and his colleagues have shown) the confession is internally inconsistent or contradicted by independent evidence.
  • PROSECUTORS stubbornly cling to false confession cases, refusing to admit the possibility of their falsity even when DNA testing unequivocally excludes the confessor. (The New York Times Magazine has more on this phenomenon, describing -- in an article titled "The prosecution's case against DNA" -- the improbable arguments manufactured by prosecutors to explain away negative DNA findings.)
  • Perhaps most dangerously, even DEFENSE ATTORNEYS succumb to the allure. Individuals who falsely confess are much more likely to be pressured into accepting a guilty plea, which bars future appeals. In an archival study conducted by Kassin and a colleague of 273 DNA exoneration cases, those based on false confessions were three times as likely to involve bad lawyering.
Matias Reyes, the actual rapist
in the Central Park Five jogger
wrongful conviction case

"Taken together," Kassin concludes, "research suggests that judges, juries, and others are doomed to believe the false confessions of innocent people not only because the phenomenon strongly violates common sense but because of corroboration inflation -- a tendency for confessions to produce an illusion of support from other evidence."

All of this suggests that it is essential for courts to allow the testimony of forensic experts who can explain the mechanisms of false confessions, including both what types of police practices are more likely to generate them, and what types of individual vulnerabilities make a person especially prone to cave in under such pressure.

More broadly, this line of analysis suggests the need for changes in police practices, for example an end to the routine practice of lying to suspects about incriminating evidence, and greater government oversight and regulation of police interrogations. Moreover, safeguards on the analysis of supposedly independent evidence, such as evidence technicians being blind to a suspect's confession status, must be implemented in order to ensure that corroborating evidence truly is independent.

The article is: "Why confessions trump innocence." Members of the American Psychological Association may download it for free as part of their member benefits; others may request a copy from the author (HERE).

Related blog posts:

For a complete list of my many other posts on the topic of confessions and interrogations, click HERE.

References:

(1)   Dror, I. E., and Charlton, D. (2006). Why experts make errors. Journal of Forensic Identification, 56, 600–616.
(2)   Elaad, E., Ginton, A., and Ben-Shakhar, G. (1994). The effects of prior expectations and outcome knowledge on polygraph examiners' decisions. Journal of Behavioral Decision Making, 7, 279–292.

Hat tip: Tim Derning

September 18, 2011

Free access to forensic articles

The Journal of Forensic Sciences, published by the American Academy of Forensic Sciences, is offering free access to select articles, including several of potential interest to this blog’s audience. Click on any of the below titles to read (and/or download) the full article.


By Janne A. Holmgren and Judith Fordham 

Abstract:  Television shows, such as CBS's CSI and its spin-offs CSI: Miami; CSI: Las Vegas; and CSI: New York, have sparked the imagination of thousands of viewers who want to become forensic scientists. The shows' fictional portrayals of crime scene investigations have prompted fears that jurors will demand DNA and other forensic evidence before they will convict, and have unrealistic expectations of that evidence. This has been dubbed the "CSI effect." This phenomenon was explored using results from a Canadian study based on 605 surveys of Canadian college students who would be considered jury-eligible and Australian quantitative and qualitative findings from a study that surveyed and interviewed real posttrial jurors. Information about the way jurors deal with forensic evidence in the context of other evidence and feedback about the way in which understanding such evidence could be increased were gained from both these studies. The comparison provides insights into the knowledge base of jurors, permitting adaptation of methods of presenting forensic information by lawyers and experts in court, based on evidence rather than folklore. While the Canadian juror data showed statistically significant findings that jurors are clearly influenced in their treatment of some forensic evidence by their television-viewing habits, reassuringly, no support was found in either study for the operation of a detrimental CSI effect as defined above. In the Australian study, in fact, support was found for the proposition that jurors assess forensic evidence in a balanced and thoughtful manner.


by Lisa L. Smith, Ray Bull and Robyn Holliday 

Abstract:  The most widely accepted model of juror decision making acknowledges the importance of both the case-specific information presented in the courtroom, as well as the prior general knowledge and beliefs held by each juror. The studies presented in this paper investigated whether mock jurors could differentiate between evidence of varying strengths in the absence of case information and then followed on to determine the influence that case context (and therefore the story model) has on judgments made about the strength of forensic DNA evidence. The results illustrated that mock jurors correctly identified various strengths of evidence when it was not presented with case information; however, the perceived strength of evidence was significantly inflated when presented in the context of a criminal case, particularly when the evidence was of a weak or ambiguous standard. These findings are discussed in relation to the story model, and the potential implications for real juries.

Forensic Identification Science Evidence Since Daubert: Part II—Judicial Reasoning in Decisions to Exclude Forensic Identification Evidence on Grounds of Reliability

by Mark Page, Jane Taylor and Matt Blenkin 

Abstract:  Many studies regarding the legal status of forensic science have relied on the U.S. Supreme Court's mandate in Daubert v. Merrell Dow Pharmaceuticals Inc., and its progeny in order to make subsequent recommendations or rebuttals. This paper focuses on a more pragmatic approach to analyzing forensic science’s immediate deficiencies by considering a qualitative analysis of actual judicial reasoning where forensic identification evidence has been excluded on reliability grounds since the Daubert precedent. Reliance on general acceptance is becoming insufficient as proof of the admissibility of forensic evidence. The citation of unfounded statistics, error rates and certainties, a failure to document the analytical process or follow standardized procedures, and the existence of observe bias represent some of the concerns that have lead to the exclusion or limitation of forensic identification evidence. Analysis of these reasons may serve to refocus forensic practitioners’ testimony, resources, and research toward rectifying shortfalls in these areas.

Additional free articles from the Journal of Forensic Sciences on a variety of forensic topics may be found HERE.

January 14, 2011

fMRI controversies: Special journal section

A special section of the Association for Psychological Science's journal, Perspectives on Psychological Science, is dedicated to controversies surrounding functional Magnetic Resonance Imaging, or fMRI, technology. The articles* are:
  • Neuroimaging: Voodoo, New Phrenology, or Scientific Breakthrough? Introduction to Special Section on fMRI by Ed Diener -- In response to the widespread interest following the publication of Vul et al (2009), Perspectives Editor Ed Diener invited researchers to contribute articles for a special section on fMRI, discussing the promises and issues facing neuroimaging.
  • Mistreating Psychology in the Decades of the Brain by Gregory A. Miller -- Scientists tend to consider psychology-biology relationships in two distinct ways: by assuming that psychological phenomena can be fully explained in terms of biological events and by treating them as if they exist in separate realms. These approaches hold up scientific progress and have important implications for clinical practice and policy decisions (e.g., allocating research funds).
  • Brain Imaging, Cognitive Processes, and Brain Networks by Brian D. Gonsalves and Neal J. Cohen -- The growth of neuroimaging research has led to reflection on what those techniques can actually tell us about cognitive processes. When used in combination with other cognitive neuroscience methods, neuroimaging has promise for making important advancements. For example, neuroimaging studies on memory have raised questions not only about the regions involved with memory but also about component cognitive processes (e.g., the role of different attention subsystems in memory retrieval), and this has resulted in more theorizing about the interactions of memory and attention.
  • Mapping Mental Function to Brain Structure: How Can Cognitive Neuroimaging Succeed? by Russell A. Poldrack -- To understand the anatomy of mental functions, researchers may to need to move away from commonly used brain mapping strategies and begin searching for selective associations. This will require more emphasis on the structure of cognitive processes, which may be achieved through development of formal ontologies (e.g., the Cognitive Atlas) that will describe the “parts” and processes of the mind. Using these ontologies in combination with large-scale data mining approaches may more directly relate mental processes and brain function.
  • The Appeal of the Brain in the Popular Press by Diane M. Beck -- Why do people like the brain so much? Brain-related articles in the press, especially ones about fMRI research, tend to be very popular with the general public, but many of these articles may result in misinterpretations of the science. Part of the popularity may be attributed to their deceptively simple message: Perform an action and a certain area lights up. In addition, people are more confident in “biological” images than in the behavioral phenomena on which the images are based. In order to maintain trust with the public, scientists have a responsibility to provide the press with descriptions of research and interpretations of results research that are clear, relevant, and scientifically accurate.
  • Frontiers in Human Neuroscience: The Golden Triangle and Beyond by Jean Decety and John Cacioppo -- The development of neuroimaging has created an opportunity to address old questions about brain function and behavior in new ways and also to uncover new questions. The knowledge that emerges from neuroimaging studies is more likely to be beneficial when combined with techniques and analyses that break down complex constructs into structures and processes, measures that gauge neural events across different times, and animal studies.
  • Bridging Psychological and Biological Science: The Good, Bad, and Ugly by Arthur P. Shimamura -- The advent of functional neuroimaging has brought both praise and criticism to the field of psychological science. Although most studies relying on fMRI are correlative, they do offer some clues about the biology underlying psychological processes. However, it is not sufficient to show which area of the brain is involved in a particular cognitive process; rather theories need to address “how?” questions (e.g., How does the hippocampus contribute to remembering?) in order to best bridge psychological and biological science.
*Note: Click on any of the highlighted author names to send an email to the author, requesting a copy of the article.

Hat tip: Ken Pope

October 21, 2010

Arson probe: "Revenge of the scientists"

Perhaps the single most compelling exemplar of problems with the U.S. death penalty is the case of Cameron Willingham of Texas. Willingham, whom I have blogged about before, was executed in 2004 for a house fire in which his three daughters perished. But, as it turned out, the fire may not have been arson after all.

An ongoing probe is fostering rebellion by scientists against pseudoscientific evidence in arson cases. Some are even calling for a re-examination of all arson convictions in Texas from the past 20 years, according to a report by Dave Mann of the Texas Observer, who has covered the case extensively.

PBS Frontline's has a new documentary on the case, "Death by Fire," which I recommend you keep an eye out for. (It's also available on DVD.) The PBS website has great background, online videos, and interactive links. PBS' Hari Sreenivasan has additional commentary and case-related links at his news blog.

Related blog posts:

August 5, 2010

The CSI Effect: An infographic

Pierce Martin of the new site, Forensic Science, just sent me this cool infographic he made about the CSI Effect, which relates to my recent post, "To catch a liar: Don't watch Fox-TV." Enjoy.

The CSI EffectSource: Forensic Science

May 4, 2010

"CSI Effect": Fact or fiction?

Since introduced by Time magazine in 2002, the "CSI Effect" has become a cultural staple, imbued with the imprimatur of fact. The judicial system and media discuss it as a grave problem; the FBI has even produced a video warning of its impact. Just last week, the Economist of London issued an uncritical report asserting the reality of the effect, based on an upcoming article in Forensic Science International.

However, as Mind Hacks pointed out, both the Economist story and the underlying FSI article rely mainly on anecdotal evidence. The scientific verdict is not yet in.

Indeed, when I last discussed the phenomenon here, two years ago, a study by Michigan Judge Donald Shelton was raising doubts. Judge Shelton found scant evidence to support claims by prosecutors that jurors' unrealistic demands for hard scientific evidence were causing unjustified acquittals. As the debate continues, I thought it time for an update.

I find it ironic that a phenomenon being blamed for injecting a biased expectation of science into the courtroom has not in itself been subjected to much scientific scrutiny. After all, anecdotes are not science; they can be used to prove almost anything.

As it turns out, some legal scholars are putting the CSI Effect to empirical scrutiny, and -- guess what -- a measurable effect in the predicted direction is hard to prove. In fact, if Crime Scene Investigation and other enormously popular forensic TV shows are having any effect, it may be in the opposite direction -- toward making juries more conviction-prone.

Mind Hacks provided links two excellent scholarly analyses, both available online and well worth reading. The first, by Simon Cole, a Criminology, Law and Society professor at UC Irvine, and doctoral student Rachel Dioso-Villa, was published last April in the Stanford Law Review. The second, by media law professor Kimberlianne Podlas of the University of North Carolina, was published in October in the Loyola of Los Angeles Entertainment Law Review.

Podlas initially devised a creative plan: She would ask prosecutors to give her details of cases in which they believed an acquittal was due to the CSI Effect; then she would have defense attorneys review the case files for alternate explanations. But, she found, 19 of the 20 cases provided to her by prosecutors had actually resulted in convictions, thereby disproving the effect.

Lacking any "real" CSI cases to analyze, she devised a mock jury case in which she manipulated the strength of the scientific evidence. She found no evidence of a difference in outcome between heavy and light viewers of the TV show Crimes Scene Investigation. As she wrote:
"What is labeled a CSI Effect may more accurately be described as a rationalization embraced by members of law enforcement who find themselves on the losing side of a prosecution. By attributing a loss to CSI's wrongful influence, a prosecutor can obtain an explanation yet maintain a belief that an acquittal was misguided. Although this cognitive rationalization is understandable, it should not be mistaken for empirical proof that the CSI Effect operates anywhere other than in the minds of those proposing it."
In their excellent critical overview, Cole and Dioso-Villa go further, suggesting a propaganda parallel between the CSI Effect and the "litigation explosion" myth promulgated in the 1970s through a well-funded insurance industry campaign against civil plaintiff's attorneys. As in that instance, popular belief persisted even after social scientists thoroughly debunked the claimed explosion in litigation:
"Tort reformers' narratives captured a much greater share of media attention than did those of scholars…. Indeed, in the wake of media claims about the litigation explosion, socio-legal scholars documented that media coverage of civil law overwhelmingly emphasized plaintiff victories and high punitive damage awards. Thus, the supposed existence of a litigation explosion became educated common sense among jurors and even judges."
Remember the McDonald's coffee spill and the microwaved poodle, urban legends still infamous today? These tales, Cole and Dioso-Villa argue, are akin to the "horror story" anecdotes of the CSI Effect, such as the supposed case in which a jury acquitted a rapist despite incriminating DNA evidence, just because soil found in the victim's cervix was not tested:
"Echoing the litigation explosion, CSI effect discourse is widely disseminating through the American public the belief that television drama is disadvantaging criminal prosecutions. And yet, the available evidence does not support this claim. Indeed, the available evidence suggests that the opposite may just as easily be the case: forensic-themed police procedural dramas may actually advantage the prosecution in criminal cases."

As shown in the above table, Cole and Dioso-Villa's analysis of several hundred media reports since 2002 revealed not one, but six claimed effects of forensic television shows on popular culture, depending upon the constituency doing the talking. The most dominant of these, the "strong prosecutor's effect," maintains that watching crime dramas makes jurors more likely to acquit guilty defendants. But, the scholars argue, the available evidence suggests an opposite effect:
"Jurors who are consumers of the popular media might believe that prosecutors are typically disadvantaged in criminal trials; that high expectations for forensic evidence are 'unreasonable'; and that criminal convictions are becoming increasingly rare and difficult to achieve. Jurors who believe these things might be more sympathetic to prosecutors out of sympathy for the perceived underdog or in attempt to correct for the perceived excesses of antecedent juries. Claiming to be disadvantaged is a familiar trope in trial advocacy, especially in opening and closing arguments; prosecutors frequently point out that they bear the burden of proof, whereas defense attorneys often refer to their lack of resources or to the awesome power of the state."
This is a similar conclusion to that of Podlas, who wrote:
"If there is a CSI Effect, narrative theory and common sense suggest that it will benefit law enforcement. CSI features the fantastical world of forensics and smart police work. …This story may cultivate the notion that forensic scientists and their methods are legitimate and reliable, thus bolstering the prosecution’s case…. Indeed, scientific evidence is very seductive to jurors, and they tend to overvalue its probity and overestimate its infallibility."
Although the CSI Effect pertains to criminal court while the Litigation Explosion myth targeted the civil realm, they share a similar distrust of jurors, that is, of the ability of common citizens to be fair and find the truth. This lack of faith, from my experience as a court observer over several decades, is misplaced.

Hat tip: Mind Hacks

October 19, 2008

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:
Check it all out here.
Photo credit: Troy & Patrice

August 19, 2008

News headlines from around the U.S.

The major news outlets are running all kinds of stories relevant to forensic psychology. Here is a sampling.

CSI counterpoint

The fallability of forensic sciences is gaining attention lately. Roger Koppl, director of the Institute for Forensic Science Administration, and Dan Krane, a biological sciences prof at Wright State, co-authored this informative op-ed piece in the Newark (NJ) Star-Ledger:


When patients kill

It is always bad news when someone is certified ready for release from a psychiatric hospital and then commits a violent offense. Take William Bruce: Two months after the 24-year-old schizophrenic was released from a hospital in Maine, he hatcheted his mother to death. Here, the Wall Street Journal finds fault with patients rights' advocates who lobbied for Bruce's release:


Christian Science Monitor slams sex offender laws

As public awareness mounts regarding restrictive residency laws targeting sex offenders, the Christian Science Monitor joins the fray with this hard-hitting editorial by C. Alexander Evans:


MoJo's "Slammed: The coming prison meltdown"

And if you've got time for still more reading, a highly recommend the Mother Jones special on incarceration, "SLAMMED." It features at least nine interesting articles, among them:





Not to mention, a "MoJo Prison Guide" with a glossary of prison slang and answers to such obscure prison trivia as:
Hat tip: Jane

April 1, 2008

Does CSI Effect really lead to more acquittals?

Crime dramas saturate network television. Most focus on science and technology, blending reality and fiction to give viewers unrealistic beliefs about evidence in real-life cases. For the past few years, prosecutors have been lamenting this so-called CSI Effect, stating that jurors are making impossible demands for scientific evidence in order to convict.

But does the expectation of scientific evidence really translate into increased acquittals? And, if so, are viewers of TV crime shows more susceptible to this effect?

Those were the questions that a Michigan judge and two other researchers set out to answer, through a survey of more than 1,000 randomly selected jurors.

Judge Donald Shelton and colleagues found that almost half of the prospective jurors surveyed expected to see scientific evidence in every case, with 22 percent expecting DNA evidence – a highly unrealistic expectation. Not surprisingly, this expectation was stronger for regular viewers of CSI, who were also more likely to believe that their favorite TV crime dramas were realistic.

However, the jurors' expectations did not necessarily translate into an automatic tendency to acquit. Rather, jurors said they would only demand scientific evidence if the prosecutor did not call the victims or others as witnesses. In rape cases, however, CSI viewers were less likely than other jurors to say they would convict a suspect in the absence of DNA evidence (which often is not available in real-life sexual assault cases).

Increased expectations of law enforcement are not necessarily a bad thing, Judge Shelton argued in an essay published in this month’s National Institute of Justice journal (available online here). Perhaps, he wrote, police should make more of an effort to get the scientific evidence that the public seeks. And, when such evidence is not available, attorneys and judges need to learn how to explain this reality to the jury.

"Most importantly," wrote Shelton, who has written extensively on the impact of technology on the law, "prosecutors, defense lawyers, and judges should understand, anticipate, and address the fact that jurors enter the courtroom with a lot of information about the criminal justice system and the availability of scientific evidence."

November 18, 2007

Call for greater regulation of expert witnesses in England

On CSI, the scientific evidence never lies. In the real world, the truth is far less clearcut. In the wake of a series of highly publicized scandals involving the testimony of expert pediatricians and pathologists, some in England are calling for more professional oversight and regulation of forensic experts. A similar scandal underway in Canada (see Saturday's blog post) could lead to calls for reform in that nation and elsewhere.

The most highly publicized miscarriage of justice in England was the 1999 conviction of Sally Clark for murdering her two children. Clark was eventually exonerated but died earlier this year of likely suicide. In that case, Sir Roy Meadow gave inaccurate testimony that the chances of Clark's two babies having died of natural causes were one in 73 million.

Today's Times of London has an article on the current legal climate vis-à-vis expert witnesses. According to the article, the British public is "clamoring" for legislation to regulate expert witnesses. "But how to do that without calling into question thousands of court decisions will not be an easy task."

Fueling this public sentiment is a recent case in which a bogus scientist, Gene Morrison, was found to have given evidence in 700 cases. Morrison, who in February received a five-year prison term, admitted he pretended to be an expert witness and bought his qualifications on the internet because it "seemed easier" than getting real ones. The Times article cites a study by a senior judge finding that most judges and lawyers do not check experts' qualifications.

But even more worrisome, the article states, has been the recent proliferation of parents convicted of causing cot deaths, shaking babies to death, or harming them by creating symptoms of fictitious illness. Social workers bristle at accusations that these cases are exaggerated, saying that the cases represent heightened vigilance in response to a previous era in which children were left to die at the hands of their parents. "In comparison with the volume of cases, the number of errors is tiny," said one social work official. "We never rely on expert witnesses alone."

The full Times of London article, entitled "The Expert as Judge and Jury," is online here.

November 17, 2007

Expert witness scandal rocks Canada

Louise Reynolds of Ontario was incarcerated for three years for stabbing her 7-year-old daughter more than 80 times with a pair of scissors. She served most of her prison time in solitary confinement to protect her from other prisoners and guards who wanted to kill her for her vicious crime. Her only visitor was the spirit of her dead daughter, who brought her ghostly comfort from the grave.

Then it turned out Reynolds had been telling the truth when she denied guilt. A pitbull had mauled her daughter to death.

William Mullins-Johnson spent more than 12 years in another Ontario prison for sodomizing and strangling to death his 4-year-old niece.

Then it turned out the little girl had died of natural causes, possibly from complications of a chronic stomach ailment.

The unifying factor identified in these and at least a dozen other wrongful convictions in Canada was the testimony of Dr. Charles Smith, one of Canada’s most renowned pediatric forensic pathologists. The revelations of Dr. Smith's erroneous findings in multiple high-profile cases has severely tarnished the image of the judiciary in the eyes of the Canadian public.

This week, Canada began a judicial inquiry into what went wrong. The hearings, expected to last several months, will examine not only the practice of pediatric forensic pathology but the broader issues of prosecutorial tunnel vision, overreliance on expert testimony, and public overconfidence in forensic science as a result of the "CSI Syndrome."

One commonality among many of the cases is the socioeconomic status of the accused, who included racial minorities, aboriginals, and single mothers, which likely stacked the deck against them.

The scandal follows a highly similar scandal in England over Sir Roy Meadows' testimony falsely accusing dozens of mothers of harming their children due to so-called Munchausen's Syndrome by Proxy. Other scandals involving expert scientific testimony have erupted in the United States, including one that I've previously posted about involving forensic odontologist Michael West of Mississippi.

Overall, these scandals are driving home the fact that experts are not infallible.

"We give great deference to experts," said Bill Trudell, chairman of the Canadian Council of Criminal Defence Lawyers. "The [Canadian] inquiry will change that and start people thinking that these experts are human and can make mistakes."

The Toronto Star has all the latest on the hearing, including a detailed list of the cases and the known facts underlying them.

Photo: Pediatric forensic pathologist Charles Smith.

October 29, 2007

ABA calls for death penalty moratorium

The American Bar Association today released findings of a three-year study on state death penalty systems and called for a nationwide moratorium on executions. Currently, more than 3,000 people are awaiting the needle, the chair, or the gallows.

In its detailed analyses of death penalty systems in eight U.S. states, the report highlights "key problems" that make the current system unfair, including racial disparities (more than 4 out of 10 death row prisoners are black, according to the U.S. Bureau of Justice Statistics), inadequate defense services for indigent defendants, and irregular processes for clemency review. The report also documents serious problems with evidence collection, preservation, and analyses; state crime laboratories are systematically underfunded and look nothing like those on television's CSI.

Of relevance to forensic psychology, the ABA's investigatory committee found that many states do not ensure that lawyers who represent mentally ill and mentally retarded defendants understand the significance of their clients' mental disabilities. In addition, jury instructions do not always clearly distinguish between the use of insanity as a legal defense and the introduction of mental disability evidence to mitigate capital sentencing.

Prosecutors and death penalty supporters are calling the study biased, saying many of the attorneys on the state investigation teams are death penalty opponents.

The full report is available online through CNN.

Chart: Capital Punishment, 2005, Bureau of Justice Statistics, U.S. Department of Justice.

September 6, 2007

Universal DNA databases looming

Racial and ethical implications debated

DNA databases are great, aren't they? In the last few years, we've heard many a case of an innocent person, languishing in prison, being exonerated by newly discovered DNA evidence. Or, we hear of DNA solving a heinous crime, perhaps even a serial murder. (We see it even more often on TV crime dramas like CSI, but that’s a story for another day.)

DNA databases work best when they contain a lot of genetic data. So, why wait until people are arrested, or even convicted of a crime? Why not swab every single person at birth, before they grow up to commit a crime?

This is not far-fetched. Such a universal database is already underway in Portugal. And now, it's being debated in England, the country that started national DNA databanking a dozen years ago. British officials already have more than 4 million samples (7% of the population, the largest proportion of any nation), and a prominent judge this week proposed cataloging everyone, even visitors to the country.

Paradoxically, proponents of universal DNA banking cite concerns of justice and fairness. The current system amounts to racial and ethnic profiling, they say. Minorities make up far more than their share of those arrested. And even when they are subsequently proven innocent or released without charges, their genetic profiles remain. In England, more than three-fourths of young black men are in the database, compared with only about one in five young white men.

When the databases first caught on in the United States, the laws contained safeguards intended to prevent this. In many states, DNA was only collected upon conviction, and only for very limited types of crimes, typically murder and rape.

But politicians, always looking to boost their tough-on-crime credentials, have expanded DNA banking to an ever-increasing array of offenses. Most recently, laws are following the British trend of collecting DNA from people who are arrested but not convicted. The U.S. Justice Department may now collect DNA from everyone they detain, a policy that will hit immigration violators hardest.

Civil libertarians are up in arms. The expanded laws are creating near-universal DNA databases for black men, they say. As criminologist Simon Cole points out, "Some demographic sectors of American society, such as poor, black, inner-city males, have shockingly low probabilities of getting through adolescence without having at least one run-in with the police. If such encounters trigger inclusion in a DNA database, the database becomes discriminatory."

Opponents also point to the possibility of wrongful incrimination. Reports of errors at DNA laboratories are becoming more common. And the possibility that DNA evidence could be planted is ever more likely. In addition, DNA contains sensitive personal information that could be exploited.

In come cases, law enforcement agencies are utilizing DNA technology in ways that are outside of public awareness or judicial oversight. For example, in an ominous new trend, when investigators cannot match a DNA profile to a crime scene, they may look for close matches and investigate those individuals' family members. Thus, a minor brush with the law can ripple through an entire family.

"In a society in which young black males in some neighborhoods have a one-in-three probability of ending up in state custody at some time in their lives (and an even higher chance of getting an arrest record), the racial overtones of such a practice are dramatic," criminologist Cole notes.

Would a universal database solve discriminatory practices, as proponents claim?

That is unlikely, so long as our criminal justice system continues to disproportionately target certain sectors of the population. In the end, DNA technology could just provide one more powerful tool for discriminatory enforcement.

Thanks to Simon Cole, associate professor of criminology, law, and society at the University of California, Irvine, for his excellent overview of this topic.

See also the American Society of Law, Medicine, and Ethics' web site, "DNA Fingerprinting and Civil Liberties."

Photo credit: Jovika (Creative Commons license)

Additional resources:

DNA and the Criminal Justice System: The Technology of Justice, David Lazer (MIT Press, 2004)

Rights and Liberties in the Biotech Age: Why We Need a Genetic Bill of
Rights, Sheldon Krimsky and Peter Shorrett(Rowman & Littlefield Publishers, 2005).

August 4, 2007

Beware the bite-mark expert

Is forensic odontologist putting innocent people on death row?

With our increasingly crime-centered culture comes the "CSI Syndrome" of glorification of all things forensic. Unfortunately, it is sometimes hard for laypeople to distinguish valid science from the junk, and good experts from charlatans.

This is especially true in newly emerging fields such as "forensic odontology," in which dentists testify as expert witnesses about bite-mark patterns.

The spotlight on wrongful convictions is shining its beam on forensic odontology as – in the words of one legal scholar – "the poster child for bad forensic science."

In an expose in the Chicago Tribune a few years ago, journalists Flynn McRoberts and Steve Mills called the field "a case study" of the ease with which "forensic science's false aura of infallibility can distort the adversarial system of American justice."

Ask 10 dentists to identify a suspect from bite marks, and six of them will point to an innocent person, according to one informal study conducted at a convention workshop back in 1999. Indeed, odontologists often don’t agree on the most basic issue of all – whether a mark on a victim’s body is even a bite mark.

Ask who is the worst culprit of all, and you’re likely to hear the name of Michael West of Mississippi. He's testified in dozens of cases and helped to send many people to prison, including at least five to death row. He’s been the subject of exposes on 60 Minutes and in Newsweek and the National Law Journal.

Later this month, his testimony will be at the center of a hearing regarding a new trial for Kennedy Brewer, convicted of the 1991 murder of his then-girlfriend's 3-year-old daughter.

At Brewer's original trial, Dr. West testified that he found 19 bite marks on the girl's body that matched Brewer’s teeth. A defense expert countered that the marks were actually insect bites, but the jury believed the charismatic Dr. West.

The new hearing is a result of new DNA technology that didn’t exist at that time. Analysis of semen found in the girl's body revealed that it came from two separate men - neither of them Brewer.

Dr. West has taken the field of forensic odontology to "bizarre, megalomaniacal depths," according to an expose yesterday on Fox News. He has "invented a system he modestly calls 'The West Phenomenon.' In it, he dons a pair of yellow goggles and with the aid of a blue laser, he says he can identify bite marks, scratches, and other marks on a corpse that no one else can see - not even other forensics experts. Conveniently, he claims his unique method can't be photographed or reproduced, which he says makes his opinions unimpeachable by other experts."

The case points to the need for both courts and professional organizations to more vigilantly police expert witnesses.

The stakes are enormously high - both for potentially innocent suspects and for the credibility of the forensic sciences. As Fox reporter Radley Balko argues:

"The Kennedy Brewer case highlights a serious flaw in our adversarial criminal justice system — the use of expert testimony in complicated, advanced scientific fields. A charlatan like Dr. West, who has little respect from his peers, can with charisma and personality convince a jury to take his word over that of an expert far more careful and deliberate in his analysis. In some cases, indigent defendants can't afford to hire their own experts at all, leaving a state's expert like West as the only testimony on the available forensic evidence."

photo credit: "selfCTRL" (Creative Commons license)