Although prosecutors said DNA evidence points to alleged rapist Antonio Burton’s guilt, the woman who analyzed the evidence has made mistakes in the past.
Prosecuting attorney Steve Redding called to the stand Thursday B.J. Khriess, a researcher with the state Bureau of Criminal Apprehension. Khriess testified that she found sperm containing Burton’s DNA on a vest owned by one of the victims.
But in cross-examination, defense attorney and DNA expert Pat Sullivan pointed out that Khriess was responsible for two errors in a previous court case that utilized DNA evidence.
Burton is charged with 11 counts of burglary, robbery and criminal sexual conduct stemming from an Oct. 8, 1996 break-in at a University apartment. During the break-in, two of the three student residents were raped, and jewelry, electronic equipment and a car were stolen.
Three other men were implicated in the incident: Victor Porter and brothers Puiassance and Giezwa Andersen, none of whom were convicted of the rapes. None of the other three men faced DNA evidence.
As if taking a beginning course in DNA analysis techniques, the jurors watched a short video about the process of genetic identification. Using terms such as Restriction Fragment Length Polymorphisms, the video was an attempt by the prosecuting attorney to make DNA testing more understandable.
Jurors took notes and scratched their chins as Khriess later attempted to show correlations between DNA taken directly from Burton and that found on a vest owned by one of the rape victims. The vest was found outside the apartment after the incident had occurred.
“What conclusions can you draw from the testimony you gave today?” Redding asked Khriess, to which she replied:
“Only Antonio Burton could have contributed the DNA.”
In a later interview, Redding said he hopes to show that Burton wiped himself with the vest after the rapes.
But in cross-examination, Sullivan attacked Khriess’ credibility as a reliable source of DNA evidence. Rifling through a three-inch folder of documents, he showed that Khriess had been involved in an incident in which two test tubes of DNA had been mixed up.
“You have made errors in your lab, is that correct?” Sullivan asked.
“There was a mix-up in the samples, yes,” she responded.
The tension level rose in the courtroom after the defense’s examination began. Attorneys approached the bench twice in five minutes and at one point the court reporter had to ask the attorneys and Khriess to speak one at a time. Numerous sustained objections from the prosecution punctuated the end of testimony after nearly six hours of continuous questioning.
Despite the complexity of the DNA evidence, however, Redding said he thought the jurors understood it. “I always look for puzzled looks, but I didn’t see any,” he said.