The decision ended Daniel Plata’s 12-year stay on Texas’ Death Row. It might also lead to the end of George Denkowski’s career as a licensed psychologist. Judge Ellis’ decision emboldened one of Denkowski’s colleagues, Jerome Brown of Bellaire, to file a complaint with the Texas State Board of Examiners of Psychologists. If Denkowski loses his license, the cases of 17 other Texas men on Death Row—men he determined were not mentally retarded—could be re-examined. And Texas’ status as a national outlier in cases involving mental retardation could be changed for good.
Brown worked as an expert for the defense on five capital cases in which Denkowski worked for the prosecution. He says Denkowski used the same estimation techniques and showed the same deference to prosecutors’ evidence in those cases as he did in Plata’s, and that it was “essentially junk science. It is science that appears to be scientific, but it doesn’t have any background of validation to it.”
One of those cases resulted in an execution. In 2005, Brown and Denkowski tested Michael Richard, who had been sentenced to death for the 1986 rape and murder of a 53-year-old Houston woman named Marguerite Dixon. Based on test scores and school records, Brown concluded that Richard was mentally retarded, and had been all his life.
At first, Denkowski agreed that Richard was mentally retarded. As the state’s expert, he had submitted a finding that Richard had an IQ of 64 and adaptive-behavior scores that clearly showed mental retardation. His combined score was a 57, well below the 70 cutoff. But Denkowski retracted his findings after prosecutors showed him a list of books that were found in Richard’s cell, including two dictionaries. Denkowski said the dictionaries showed that Richard could read much better than he had indicated under testing. He adjusted several of Richard’s scores. When he added them up, the total score jumped from 57 to 76. In his new opinion, Denkowski concluded that Richard should no longer be considered mentally retarded.
When Brown saw the prosecution’s list of books, he met with Richard a second time to ask him about his reading abilities and clarify how he’d used the books in his cell—one of which was written in German. Denkowski had not followed up with Richard to ask about the books. Richard described to Brown how he stacked the books on top of each other and used them to sit on, since his death row cell lacked a chair.
Even so, the judge accepted Denkowski’s revised score. In September 2007, Richard was executed. Brown was appalled. “To those of us familiar with the right way to do these things, it is very apparent that what he’s doing is wrong.”
After the judge rejected Denkowski’s findings in the Plata case, Brown enlisted Jack Fletcher and a Florida-based psychologist named Tom Oakland to jointly file a complaint against Denkowski. Oakland co-authored the adaptive-behavior test. Their complaint cited the Richard case, as well as those of Plata and DeWayne Brown.
Last February, the state Board of Examiners of Psychologists upheld the complaint, finding that Denkowski had made “administration, scoring and mathematical errors” in all three cases. The board sent the complaint to the State Office of Administrative Hearings. Denkowski will have a chance to defend himself in a hearing scheduled for Feb. 16 in Austin. He could lose his license.
The broader psychological community has also rejected Denkowski’s methods. He is mentioned by name in the 2010 edition of the American Association on Intellectual and Developmental Disabilities’ diagnostic manual. In a section about how cultural or economic factors should impact scores on adaptive behavior tests, the authors “strongly caution against practices such as those recommended by Denkowski.”
Denkowski’s career as a prosecution expert appears to be over, whatever the outcome of his hearing. The Harris County District Attorney’s office stopped using him after Plata’s death sentence was overturned.
No other counties have hired Denkowski to work on Atkins cases since 2008. But the impact of his previous work continues to unfold. In October 2009, the U.S. Fifth Circuit Court of Appeals put the Atkins appeal of Steven Butler on hold pending the outcome of Denkowski’s hearing. In November a federal district court put another appeal, that of Joel Escobedo, on hold for similar reasons. And in December, the Fifth Circuit found that a lower court had “erred” when it dismissed Anthony Pierce’s right to a hearing based on Denkowski’s role in denying his Atkins claim. Several similar requests to put appeals on hold are pending.
Daniel Plata’s lawyer, Kathryn Kase, argues that all of the appeals on which Denkowski worked should be re-heard. “When you have junk science in a case, it’s like pouring poison into a punch bowl,” she says. “You aren’t going to get the poison out. So you have to pour out the punch, clean the bowl, and start all over again.”
Renée Feltz is an investigative reporter living in New York City. Research support for this article was provided by the The Nation Institute’s Investigative Fund. Special thanks to Gislaine Williams, Bryan Parras, Claire Loe and Tish Stringer for their assistance with translation and equipment.