Avoiding Confrontation with DNA

June 19, 2012
Guest Post

By Brandon L. Garrett, a professor at the University of Virginia School of Law. Garrett’s book, Convicting the Innocent: Where Criminal Prosecutions Go Wrong, is coming out in paperback later this summer, and updates are at the book’s Facebook page here.


Yesterday the Supreme Court Justices splintered over the meaning of the Confrontation Clause in cases involving forensic DNA testing – making a muddle of an important problem and with few discernible arguments that hold much water. The case involved a sexual assault, but the Illinois State Police did not test crime scene evidence – they tested a sample of blood from the suspect and obtained his DNA profile. The evidence from the rape kit was DNA tested by an outside lab, Cellmark. The prosecutor did not call the Cellmark technician at trial, the one who did the most important DNA testing in the case, the testing that identified the DNA profile from the semen of the assailant. Instead, the prosecutor called the crime lab technician who described the defendant’s profile – and sneaking the match in through the back door, by having that technician say how it matched the profile identified in the Cellmark report. The DNA was central evidence at trial, although the victim also identified the defendant in a line-up. The defense had no opportunity to cross-examine the Cellmark analyst who did the crucial DNA work.

The case called for a straightforward application of the Court’s recent precedents in the Confrontation Clause area. Just last year, the Court held in Bullcoming v. New Mexico, a case where DUI test results were not presented by the technician who did the tests, that this was a Confrontation Clause problem. The defense must have an opportunity to cross-examine the person who did the relevant work. That decision reinforced the Court’s 2009 decision Melendez-Diaz v. Massachusetts, stating that the Confrontation Clause requires live testimony, not merely introduction of a certificate stating the conclusion of a forensic test used to identify drugs. 

The new answer to the question of whether a forensic DNA analyst must testify is “maybe.” Justice Alito, joined by Chief Justice Roberts and Justices Kennedy and Breyer, argued that this was a bench trial before a judge – and the DNA testimony was reliable since it merely reported the way that testing confirmed results prepared as part of the criminal investigation. Justice Alito suggested the DNA report was not prepared to incriminate anyone, an odd claim. Justice Alito also suggested that a “modern” and “accredited” laboratory is presumptively reliable. Justice Breyer added that if a defendant could sufficiently question the reliability of a lab or its report, then the defendant could recover their Confrontation Clause right – what showing that would require is anyone’s guess. Justice Thomas switched his vote from the prior two, adopting a rationale that none of the others joined, arguing Confrontation Clause rights attach only to sufficiently “solemn” reports, whatever that means. He did strongly disagree, though, that DNA tests should somehow be treated differently for Confrontation Clause purposes.

In dissent, Justice Kagan began with a California case where an analyst from Cellmark made an outright mistake – which was only discovered during cross-examination at a trial. Justice Kagan then pointed out: “a defendant may wish to ask the analyst a variety of questions: How much experience do you have? Have you ever made mistakes in the past? Did you test the right sample? Use the right procedures? Contaminate the sample in any way? Indeed, as scientific evidence plays a larger and larger role in criminal prosecutions, those inquiries will often be the most important in the case.” 

The danger of wrongful convictions played an odd role in the plurality opinion. Both Justice Alito’s plurality opinion and Breyer’s concurring opinion claimed that requiring the prosecution to put on testimony by additional DNA analysts could somehow “also increase the risk of convicting the innocent,” because burdened in the presentation of DNA, prosecutors would just rely on evidence like eyewitness evidence. As the author of a book, “Convicting the Innocent,” and having studied what happened in the trials of people exonerated by DNA, I found this claim quite surprising. I was honored Justice Breyer cited to my research on the fact that exoneree trials had a parade of invalid and unreliable forensics (and concealed and erroneous forensics, among other problems.)  Nor did exoneree defense lawyers often understand the problem and make good use of cross-examination. But the notion that burdening presentation of DNA evidence would cause prosecutors to rely on less reliable forms of evidence is absurd. There are very, very few criminal trials, and simply putting the relevant technicians on the stand is a minor expense (indeed even in the rare trial, defendants may rather stipulate so the jury will not hear damning testimony).  Nor did the Justices suggest improving the reliability of eyewitness evidence last Term in Perry v. New Hampshire, much less forensic evidence in this case. That aside, Justice Kagan hit the nail on the head when she pointed out that, “Neither opinion provides any evidence, even by way of anecdote,” that prosecutors might somehow become less likely to use DNA, and adding, “I doubt any exists. DNA evidence is usually the prosecutor’s most powerful weapon, and a prosecutor is unlikely to relinquish it just because he must bring the right analyst to the stand.”

To be sure, the underlying problems facing forensics today require far more than a Confrontation Clause right to cross-examine.  Few cases go to a trial, and problems of quality control at laboratories, unreliable methods, and invalidity of forensic techniques have not gone away at all in our DNA age. In 2009, the landmark National Academy of Sciences report, “Strengthening Forensic Science in the United States: A Path Forward,” explained how the bulk of forensic techniques in wide use today, with the exception of nuclear DNA testing, cannot consistently and validly be used to link evidence with a particular defendant. Congress has yet to act on those important recommendations. As I have noted before, even in the cases that do go to a trial, the defense cannot meaningfully question the analyst about the work they did in the lab, unless judges do far more to ensure that the defense has access to underlying bench notes describing the lab work (and not just the final lab report announcing the result).  Defense lawyers are routinely denied forensic experts of their own, so they have no way to meaningfully examine the work that the prosecution analyst did or offer a second opinion. 

One important statement in the plurality opinion was the statement emphasizing that a crucial safeguard is that judges “strictly enforc[e] the requirement that experts display some genuine “scientific, technical, or other specialized knowledge.”  Now that the Court has moved away from an unqualified defense right to cross-examine in rare cases that go to trial, unless judges do more to strictly ensure access to discovery, defense experts, and gatekeeping of the reliability of evidence, we will continue to see mounting wrongful convictions and forensic scandals.