DNA tests useful in the courtroom, UA prof says
DNA testing is one of the premiere methods of separating the guilty from the innocent in criminal trials, a UA professor said yesterday.
"It's well known in criminology that eyewitness testimony is not always completely accurate," said Richard Hallick, a biochemistry professor who spoke to about 80 people in the UA's Gallagher Theatre. "DNA is the best way to exonerate someone falsely accused of a crime."
Hallick gave the lecture entitled "DNA Evidence in Criminal Trials" as part of the weekly Building Academic Community speaker series.
Primary suspects in about 25 percent of criminal court cases are cleared of crimes thanks to scientific tests, he said.
As an expert in that type of work, Hallick said he has testified about 30 times in criminal trials since 1991.
"The courtroom is an unusual environment for scientists to be in," he said.
Through a slide presentation, Hallick demonstrated that law enforcement, along with scientists, can compare DNA strands in an effort to identify suspects and eliminate the innocent.
"Semen from sexual assaults are the most common form of evidence," he said.
Other substances used for testing include blood, bone marrow, hair, saliva, urine and tooth pulp, he said.
Hallick said he was once involved in a case in which blood was taken from the trunk of a suspect's car and matched with evidence from a body found in the Sonoran desert.
The suspect was later convicted of murder, which was supported by the scientific data, he said.
"If you can find matches ... you can say with a very high probability that they are from the same person," he said.
Hallick described a recently-constructed computer database that holds personal scientific information about suspects. Computers will also aid in identifying the deceased, he said.
"We will probably never have another unknown soldier in this country," Hallick said, as he displayed a slide of the Tomb of the Unknown Soldier in Washington D.C.
But he said Americans looking for insurance might be adversely affected because Health Management Organizations now have joint use of personal medical data.
When people take tests showing that they could get a life-threatening disease in the future, insurance companies may avoid offering adequate coverage, he said.
Americans are often forced to pay for private medical tests through their computers, Hallick said.
"Some people who have a legitimate need for DNA testing are resorting to the Internet," he said.
Hallick referred to the O.J. Simpson murder trial, and what he found to be problems with the Los Angeles jury's determination that Simpson did not kill his ex-wife, Nicole Brown, and her friend.
He said there was never an explanation for the presence of blood leading out of Brown's house.
"A criminalist would probably testify that it's a certain match," he said. "I don't think the verdict rested on scientific evidence."
Liz Dailey can be reached via e-mail at Liz.Dailey@wildcat.arizona.edu.