Posts Tagged ‘DNA testing’

The National Registry of Exonerations, a joint project of the law schools at University of Michigan and Northwestern, reported last week that in 2012, law enforcement cooperated in some way in a higher percentage of cases than in the past.  Does this mean less resistance of science by law enforcement?

The answer is that we can’t tell from this data.  But the report is worth looking at nonetheless.

Here is what the report says about law enforcement cooperation (I have removed the bullets, spacing, etc.):

In  2012 there was a dramatic increase in the number and the proportion of exonerations that prosecutors or police participated in obtaining.  Of the 63 exonerations in 2012, prosecutors or police initiated or cooperated in 34, or 54%. Over the past 24 years, prosecutors and police have cooperated in 30% of the exonerations we know about (317/1050). Last year for the first time they cooperated in a majority of exonerations, and the number of such cases is a large increase from the previous high (22 of 57 in 2008, or 39%).

This is all to the good.  But there are some aspects of the findings that counsel caution.  First, the author(s) of the report freely admit they don’t know why  this is happening.  It could have many causes.

This increase [in cooperation] may be due to a confluence of related factors: changes in state laws that facilitate post-conviction DNA testing, the emergence of Conviction Integrity Units in several large prosecutorial offices, and, perhaps, a change in how law enforcement officers view the possibility of false convictions at trial.

And just to be clear, it’s good that they admit that it’s not clear what the cause or causes could be.  Too often, those working with statistics take an opposite tack.

As far as resistance to science, however, the report may indicate that the cases where science and forensics matter most still do not get cooperation for law enforcement.  The first clue is that 57% of the exonerations in 2012 were homicide cases, and another 24% were sexual assaults — 81% in all.  These are the types of cases in which resistance science on eyewitness identification, interrogation, and  forensics can matter the most.  These cases also have the highest public profile.  And there, perhaps, is the rub: “Official cooperation is least common among exonerations for highly aggravated and publicized crimes – murders with death sentences and mass child sex abuse prosecutions – and most common among exonerations for robberies and drug crimes.”

The best way to answer whether this increased cooperation represents any lessening of the resistance to science would be to look at the individual exoneration cases for 2012: do they feature law enforcement cooperation over these science-based issues, or is it something else — for example, information on a witness interviews illegally withheld from the defendant in a previous trial?

Perhaps we will see that in the next report from the Registry.

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In yesterday’s post, I discussed Maryland v. King.  Those arguments,  heard at the Court on February 26, considered whether a state should be permitted to take a DNA sample from every person arrested (not convicted — arrested) for a felony.  I asked in my post that we put questions of  individual privacy aside, and instead ask whether such wide sampling would be a good idea from a crime-solving point of view.  (Some experts do not think so, as discussed in the post.)

Today, let’s put the question of privacy back into the equation, because that appears to be what the Justices will do.

In his recap of the Feb. 26 argument, Scotusblog’s Lyle Denniston tells us that the key points were posed by two of the Court’s conservative justices.  According to Denniston, Justice Samuel Alito clearly favored the idea that law enforcement should be able to take these samples.  DNA sampling “is the 21st century fingerprint” Alito said at least twice.  According to his way of thinking, there is no constitutional difference (in terms of the degree of intrusion on individual privacy) between taking a fingerprint and taking a DNA sample.

The other pole of the argument was taken up by conservative icon Justice Antonin Scalia.  When the lawyer for the state of Maryland used a long list of cases solved through DNA testing to support her argument in support of the law, Justice Scalia reacted forcefully.  According to the National Law Journal:  “Well, that’s really good!” Scalia exploded. “I’ll bet if you conducted a lot of unreasonable searches and seizures, you’d get more convictions, too. That proves absolutely nothing.”  In other words, the question isn’t whether the state’s action solves cases; some methods of solving cases are simply not allowed under the Constitution, even if they could be proven to work better than others.  The question is whether the Constitution — in this case, the Fourth Amendment’s prohibition of unreasonable searches — allows the state to do what it wants to do.

During Tuesday’s argument, Justice Alito commented that King could be “the most important criminal procedure case this Court has had in decades.”  That will depend on how the Court decides the case, which it will do sometime before the end of June.  But one thing we do know:  the debate between law enforcement’s desire to use all the tools it can to fight crime and the Constitution’s protections of the individual against state intrusion will go on.

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.