Lawyers defending Scotland E. Williams against double-murder charges started laying the groundwork Friday to try to show that the laboratory that did genetic testing for prosecutors and police had worked on contaminated samples and had tried to hide that from the defense.
But the jury in Anne Arundel County Circuit Court also heard from a lab employee that a key piece of evidence -- a drinking glass taken from the victims' Winchester on the Severn home near Annapolis -- had not been contaminated and did show evidence of DNA similar to Williams'.
Williams, 35, of Arnold is accused of the execution-style shootings of married lawyers Jose E. Trias, 49, and Julie N. Gilbert, 48, found dead in their bed May 16, 1994. Videotapes the jury saw Friday depict him using what bank officials testified last week were the victims' ATM cards. Other evidence shows what prosecutors say were his shoe print, hair and glove fibers found in the victims' house.
Williams was convicted of the murders in 1995 and sentenced to death, but the Maryland Court of Appeals reversed the conviction in 1996, ruling that unfair testimony and evidence against Williams had been allowed at the same time that defense moves to challenge the DNA evidence had been rejected. Prosecutors again are seeking the death penalty.
The defense began making its challenge to the DNA evidence Friday in pointed questioning of Melissa Weber, who performed the genetic tests at Cellmark Diagnostic Inc. She was grilled rTC about recordkeeping, laboratory practices and the company's racial genetic databases, used to determine how widespread certain genetic traits are within a particular group.
Weber, who no longer works for Cellmark, said laboratory directors ordered lab workers to keep a contamination log for several months.
The log became a huge defense issue last fall, because lab officials said that if they had one, it was informal and no longer existed. But at Thanksgiving, the log was discovered and turned over to prosecutors, who gave copies to the defense.
In the log, Weber noted contamination in one test for the Williams case -- cells taken from the dashboard of Gilbert's car -- and on the witness stand she said she'd forgotten to note a second instance.
But, Weber said, there was not enough DNA from the dashboard to work with. And Williams' attorneys acknowledged that he had been the person photographed at a bank window behind the wheel of Gilbert's car.
In the second instance, Assistant State's Attorney Anne Colt Leitess said tests on a cigarette butt found outside the house were inconclusive.
Cellmark, in Montgomery County, is the largest independent forensic DNA testing laboratory in the United States and is viewed as the blue-chip private lab for DNA "fingerprinting" by many in the forensics industry.
Cellmark overhauled its genetic database for African-Americans last year, removing 19 samples that either could not be confirmed as coming from people who were black Americans or whose blood for testing came from a blood bank, according to Weber's testimony. Defense attorney Michele Nethercott asked Weber if she knew why the database had been reviewed, but Weber said she'd heard nothing about that.
As the case progresses, Nethercott is expected to try to show that the database of 100 African-American people is insufficient and that Cellmark does not maintain detailed contamination records.
Pub Date: 5/17/98