Trial highlights pitfalls and promise of cold-case DNA evidence - The San Diego Union-Tribune

The forensic results landed loudly. DNA on sperm cells in a murder case came back to one of the San Diego Police Department’s own employees: a worker in the crime lab.

“We were in a very difficult spot,” said Patrick O’Donnell, a lab supervisor.

What the police did next is central to a civil-rights and wrongful-death lawsuit unfolding in San Diego federal court. The worker linked to the crime, Kevin Brown, 62, killed himself while he was under investigation. His widow is suing the lead detective, accusing him of recklessly ignoring accidental cross-contamination in the lab as an explanation for the DNA.

Over three days of testimony last week, a string of criminalists — Brown’s former colleagues, current lab employees, a private DNA consultant — came into court and said that contamination was possible. The consultant called it “more likely than not.” Happens in even the best labs, they said. Numerous examples of it occurring in the San Diego lab since 2001 got discussed.

Advertisement

But that’s a message that may not have made it to the homicide investigators. Michael Lambert, the lead detective, testified that he was told when he got the case that contamination had been ruled out already. He said he didn’t know, until about two weeks before Brown committed suicide, about a possible source for the sperm: Lab employees routinely kept their own semen samples at work to use in testing.

A jury of five men and two women is hearing the case in front of U.S. District Court Judge Dana Sabraw. Testimony resumes Monday.

The murder happened in August 1984. Claire Hough, 14, was found strangled, her body mutilated and her mouth stuffed with sand, at Torrey Pines State Beach. During her autopsy, swabs were taken from her body cavities and given to the police lab.

Back then, DNA testing — the linking of biological evidence to specific suspects — was still several years away. The police lab did more general screening of clothing and other items, looking for the presence of various bodily fluids and identifying blood types.

Advertisement

To make sure test chemicals worked properly, criminalists testified last week, they routinely used and shared their own “standards” — dried semen kept on small pieces of cloth and stored in envelopes in a lab refrigerator. They didn’t always wear masks and gloves, and they washed their scissors and other instruments with water or alcohol instead of bleach, which is known now to be better at preventing contamination.

“There wasn’t anything unusual about it,” testified James Stam, a former lab supervisor. “That’s just the way things worked.”

When the vaginal swab from Hough’s autopsy was tested in 1984, no sperm was found. Subsequent testing, in 1999 and 2006, located a few cells. Then, in November 2012, more sophisticated DNA techniques isolated an estimated 150 sperm cells (the average ejaculate has hundreds of millions) and identified Brown, who worked in the lab from 1982 to 2002, as the source.

A month later, the investigation was handed to Lambert, a department veteran of almost 24 years.

Contamination downplayed?

Now retired, Lambert took the witness stand Friday afternoon and is expected to continue his testimony Monday.

Witnesses are usually kept from the courtroom until they testify, but Lambert is a defendant in the lawsuit, which means he’s been sitting every day at a table with the deputy city attorneys representing him.

From there, Lambert heard Stam last week recount a conversation the two had after the DNA results came in. “I told him Kevin didn’t do it,” Stam said. “It was contamination.”

He heard O’Donnell testify that in his meetings with the detective, he told Lambert contamination had to be examined as an explanation for the DNA hit. “I never took that off the table,” O’Donnell said.

Advertisement

David Cornacchia, the criminalist who did the DNA tests that implicated Brown, said he, too, advised Lambert that contamination was a possibility, and suggested he talk to people familiar with how the lab operated when the vaginal swab was collected.

It’s unclear when those conversations took place. Lambert testified that he didn’t always memorialize them in reports. He also said he didn’t speak with John Simms, the criminalist who first examined the Hough evidence in the police lab in 1984. Simms testified that it’s possible he used Brown’s semen sample while checking the efficacy of the chemicals, perhaps failed to completely clean his scissors, and inadvertently transferred cells to the vaginal swab.

“I don’t want to believe I made a mistake, but I have to admit it’s a possibility,” Simms said.

All of that’s important because the lawsuit alleges that Lambert intentionally downplayed the possibility of contamination when he convinced a judge to sign a search warrant for the Brown home in Chula Vista in January of 2014. If he hadn’t made misstatements and omissions, the suit claims, no judge would have found probable cause and allowed the search, and as such, Brown’s constitutional rights against unlawful search and seizure were violated.

A dozen police officers removed 14 cardboard boxes and four plastic trash bags of items from the house, including tens of thousands of photos and memorabilia that belonged to Brown’s wife, Rebecca, and her mother. Judge Sabraw has already ruled that the search was illegally overbroad.

Lambert testified that nothing was found linking Brown to Hough or to Ronald Tatro, a convicted rapist, now deceased, who also was tied to the murder through DNA testing in 2012. His blood was found on the victim’s clothes. Lambert suggested during the investigation that the two men traveled in similar circles, such as strip clubs, but no evidence connecting them has been found.

According to the suit, Brown — who suffered from anxiety and depression for much of his life — began to unravel as months went by and Lambert declined to return the items taken in the search. Herbert Selby, a former neighbor, testified that Brown took that as a sign he might be arrested and charged. “He was like a little scared rabbit,” Selby said.

On Oct. 20, 2014, 10 months after he was first contacted by police about the murder, Brown hanged himself from a tree in Cuyamaca Rancho State Park. There was no suicide note.

Advertisement

City’s case next

The testimony so far has come from witnesses called by Rebecca Brown’s legal team, headed by Eugene Iredale. In his opening statement last week, he told the jury, “This is about the value of a human life and the value of the constitutional rights that are supposed to protect us all.”

Attorneys for the city will present their case-in-chief this week. In addition to Lambert, they are representing Maura McKenas-Parga, another retired detective. She helped oversee the search of the house.

In her cross-examination of witnesses last week, Catherine Richardson, a senior chief deputy city attorney, focused on several points. Although witnesses said Brown kept his own semen sample in the lab, there are no logs, photos or other evidence to prove it. Similarly, although Simms testified that he thinks it’s possible he “flubbed” and allowed contamination to happen, he said he has no specific recollection of testing the Hough evidence.

Richardson has asked witnesses whether they know of any other case in which a lab worker’s sperm has inadvertently contaminated a piece of evidence, and they’ve all said no.

In her opening statement, she said the case isn’t about who killed Hough, or whether contamination happened in the lab. “What this case is about is what Mr. Lambert knew or didn’t know” as he investigated the case for a year before getting the search warrant. She called that investigation “fair and reasonable,” an attempt to bring justice to Hough’s family, and said it didn’t lead to Brown’s suicide.

Instead, she pointed to Brown’s “own actions,” including what the detectives viewed as incriminating statements during interviews, and to the actions of some of his relatives, who thought he might be guilty and was probably going to be arrested. “Bye bye, Kevin,” one of them reportedly said.

Let's block ads! (Why?)

"case" - Google News
February 08, 2020 at 08:02PM
https://ift.tt/38d7PdB

Trial highlights pitfalls and promise of cold-case DNA evidence - The San Diego Union-Tribune
"case" - Google News
https://ift.tt/37dicO5
Shoes Man Tutorial
Pos News Update
Meme Update
Korean Entertainment News
Japan News Update

Bagikan Berita Ini