Failed Evidence Reviewed by the American Criminal Law Review

The current issue of the American Criminal Law Review has a review essay of Failed Evidence: Why Law Enforcement Resists Science (2012).   According to the review, the book “engages…broadly with forensics” to explore “why law enforcement and prosecutors have shown such marked reluctance to incorporate a modern understanding of the scientific method.”  The review concludes that Failed Evidence “provides a thoughtful analysis of the scientific bases underlying forensics, current evidentiary and investigatory problems, and possible solutions. [The] suggestions are particularly well thought-out because they consider the problems faced by law enforcement when implementing ideal solutions in the real world.”

You can read the full review here.

Put Privacy Aside: Is Collecting DNA From Every Arrested Person a Good Idea?

Today the U.S.  Supreme Court hears arguments in Maryland v. King, the Court’s latest foray into  DNA testing.  Most reports have focused on the clash between law enforcement’s desire to test every arrested person in order to try to solve old cases, and those who advocate for a strict interpretation of the Fourth Amendment’s protection of privacy.  For example, a report by the excellent Nina Totenberg of National Public Radio discussed the positions of police, who believe taking a sample from every person arrested is a minimal intrusion that can have a big payoff, and the arguments of defense attorneys and civil libertarians, who feel that allowing testing of all arrestees would surrender the basic principles of the Fourth Amendment’s protection against unlawful searches and seizures.

But there’s a question that may be far more important: from a crime fighting point of view,   is it a good idea for police to take and process a DNA sample for everyone who gets arrested?   Of course there will be some cases — such as the King case itself — in which the time-of-arrest sample leads to an arrest for a different, serious crime.  But taking samples from every arrestee may actually hurt our efforts to use DNA most effectively to make ourselves safe.  According to an article in Slate by Brandon Garrett and Erin Murphy, real public safety gains from DNA lie not with taking samples from every jaywalker and burglar and hoping for a hit in a cold case, but instead in taking many more samples from crime scenes.  In other words, we get more hits when we process samples from active crime scenes and match them against our already-large DNA database, instead of fishing for leads among the whole population of more than 12 million people arrested every year.  And all of those additional samples from arrestees crowd out and slow down the processing of samples from real crime scenes and victims, creating backlogs.  In other words, bigger DNA databases is not the answer to crime.

[B]igger is only better if DNA databases grow in the right way: by entering more samples from crime scenes, not samples from arrestees. DNA databases already include 10 million-plus known offender profiles. But a database with every offender in the nation cannot solve a crime if no physical evidence was collected or tested.  And police collect far too few such samples….The police solve more crimes not by taking DNA from suspects who have never been convicted, but by collecting more evidence at crime scenes.  Even worse, taking DNA from a lot of arrestees slows the testing in active criminal investigations….Backlogs created by arrestee DNA sampling means that rape kits and samples from convicted offenders sit in storage or go untested.

The bottom line: even if the Supreme Court says we can take a sample from every person arrested, doesn’t mean we should.

 

“Failed Evidence” Selected By delanceyplace.com, the Non-fiction Book Source

Good news: Failed Evidence: Why Law Enforcement Resists Science is the Feb. 4 selection by delanceyplace.com, a service that highlights and quotes new works for a large community of readers.  Delancyplace.com provides daily subscribers with “an excerpt or quote we view as interesting or noteworthy, offered with commentary to provide context. There is no theme, except that most excerpts will come from a non-fiction work, primarily historical in focus, and will occasionally be controversial. Finally, we hope that the selections will resonate beyond the subject of the book from which they were excerpted.”  Other recent selections have included Jared Diamond, The World Until Yesterday: What Can We Learn from Traditional Societies; Gordon Wood, Empire of Liberty: A History of the Early Republic, 1789-1815; and Ray Kurzweil and Terry Grossman, Transcend: Nine Steps to Living Well Forever.

 

Bite Mark Analysis: The Biggest Fail of All Failed Evidence

Among failed forensic methods, virtually no type of evidence that has a worse record than bite mark analysis.

In my book Failed Evidence (NYU Press, Sept. 12), I say that courts must simply stop accepting bite mark analysis.  It has no scientific basis whatever, and has been the source of numerous wrongful convictions.  Now, a practitioner of this, um, method has spoken out, and lo and behold, I find myself agreeing with him.  That’s because he now says there is nothing to it.  Of course, this comes after years of testifying to the bite-based guilt of defendants in “dozens” of cases.

With thanks to the Innocence Blog, I see that Dr. Michael West of Hattiesburg, Mississippi, whose bite mark work has sent defendants to prison and even death row, no longer thinks bite mark analysis has any validity.  A Mississippi newspaper reported that in a 2011 deposition, West said that that “I no longer believe in bite-mark analysis.”   In fact, he went further:  ”I don’t think it should be used in court. I think you should use DNA. Throw bite marks out.”

Forensic odontology — the study and analysis of teeth for legal purposes — can be a useful tool.  For example, it is often used, quite successfully, to identify human remains when nothing else can.  But analyzing bite marks to identify perpetrators of crime has never had any scientific validity, and has been proven incorrect in case after case after so-called experts like West used bite marks to send innocent  men and women to jail.

It’s worth noting that, even as West now disavows bite mark analysis, he somehow maintains that his work was correct.  In two different cases of raped and murdered children, West’s bite mark testimony put two defendants behind bars, one on death row for 15 years, the other in prison for 18 years.  When DNA proved that another man had committed both crimes, West refused to back down.  ”I never accused them of killing or raping anybody – just biting them while they were alive.”

Along with the reversal by the remarkable Dr. West, there’s news on the Wrongful Convictions Blog that Douglas Prade, a former police captain from Akron, Ohio, convicted of killing his ex-wife in  a 1998 case largely on “bite mark” evidence, has been exonerated based on DNA.

There is only one real question about bite mark evidence: when will courts ban it?  When is enough damage enough?

 

Forensic Linguistics: DNA for Language or More Failed Forensics?

In the July 23 issue of The New Yorker,  ”Words on Trial” introduces us to forensic linguistics.  Linguists, it seems, can now harness their knowledge to solve crimes.   The article describes a number of cases in which linguistic patterns expose who, or in some cases who did not, commit crimes that police could not solve.

It is an intriguing idea: linguists analyze various sorts of patterns and usages in writing and speaking.  With writings, they detect patterns that can go a long way toward identifying the author of a ransom note or a threat.

For me, what was so striking was how the same old forensic science questions from fingerprint analysis, tool marks, and hair and fiber comparisons emerge in this very new forensic discipline.  Is this a field the power of which is based on human interpretation, in which the experience and knowledge of the analyst rules, as is true with fingerprint analysis? If so, does it suffer already from the same deficiencies?  Or should forensic linguists strive for a data-based standard, such as DNA?  Both approaches are on display in the article, though the former is featured as the probable future of the field.

After looking hard at the 2009 NAS report, we should be cautious about introducing another forensic methodology that cannot quantify its error rate, cannot state the probability that the answer it gives is correct, and therefore cannot truly state whether or not a particular piece of writing is in fact associated with a defendant.  One forensic linguist says that he does not testify that he knows who wrote the items he analyzes; he will only say that the language in a given item “is consistent with” the language in the defendant’s other writings.  The caution is absolutely appropriate, but I wonder whether a jury will overlook this nuance, and simply hear “it matches.”

Every new tool that promises to solve crimes deserves serious attention; some new methods will make the world safer from predators.  But let’s not take these new tools where we have gone blindly before — into the land of failed forensics.  Instead, courts should accept them only when they can actually claim to use rigorous methods that support their claims.  Anything else will just generate a new wave of wrongful convictions.

DNA as failed evidence: When is a match not a match?

DNA evidence has become a forensic tool of precision and power in the criminal justice system.  Nothing can touch its scientific pedigree, the strength of its ability to make an identification, or its rigorous protocols for collection, analysis, and presentation of probability-based evidence.

But something new is on law enforcement’s radar: using DNA in a way that brings us back to the bad old days of using the blunt instrument of serology to “match” a perpetrator to the crime.

In July 5′s Chicago Tribune, reporter Steve Mills’s article, “Weak DNA Evidence Could Undermine Justice, Experts Say,”, tells the story of Cleveland Barrett, who was arrested for a predatory criminal sexual assault on a 9-year-old girl.   Part of the evidence against Barrett: according to prosecutors, DNA showed Barrett committed the crime.

But this wasn’t the kind of millions- or billions-to-one DNA identification we’ve grown accustomed to seeing, because prosecutors were using tiny amounts of DNA in an unusual way.  According to Mills’ story, the DNA used in Barrett’s case

was different. It was not from semen, as is often the case in rapes; instead it came from male cells found on the girl’s lips. What’s more, the uniqueness of the genetic link between the DNA and Barrett was not of the 1-in-several-billion sort that crime lab analysts often testify to in trials with DNA evidence. Instead…the genetic profile from the cells matched 1 in 4 African-American males, 1 in 8 Hispanic males and 1 in 9 Caucasian males.  Fact is, the DNA profile from the cells on the victim’s lips could have matched hundreds of thousands of men in the Chicago region.

And yet, the prosecutor’s closing argument used the word that juries know signifies an almost irrefutable, scientifically solid identification: “match.”

The use of weak DNA evidence like this is “preposterous” and has “almost no value at all as evidence,” according to Edward Blake, a leading DNA authority quoted by Mills.

Just what the criminal justice system needs: a way to make some of the most powerful scientific evidence ever devised into misleading junk science that claims to “match” a defendant to a crime.  Law enforcement resists existing science that can make its basic procedures like eyewitness identification, interrogation, and forensics better; yet it seems determined to push one of its best tools away from scientific precision, and toward inaccuracy.