Burlington, N.C. — The head of a private laboratory where DNA evidence in the Duke lacrosse case was tested no longer works there.

The move comes less than a month after the former defendants filed a federal civil rights lawsuit against Dr. Brian Meehan, former District Attorney Mike Nifong and several others involved in the investigation.

Civil attorneys allege they were part of a "DNA conspiracy" and purposely withheld potentially exculpatory evidence that could have been used to clear their clients of the criminal charges against them.

Neither Meehan nor his attorney would talk Monday about why he was replaced.

DNA became the focus of the yearlong investigation against David Evans, Collin Finnerty and Reade Selgimann, and, ultimately, helped clear them of the charges they faced. Making misrepresentations about DNA evidence in court also sent Nifong to jail for criminal contempt.

Meehan helped found the Burlington lab, DNA Security Inc., in 1998 and served as its director. He was the one who tested the 46 DNA samples from the 2006 Duke University men's lacrosse team and found no matches to DNA collected from the exotic dancer who claimed she was raped, sexually assaulted and kidnapped at the March 14, 2006, lacrosse team party.

He did, however, find male DNA on evidence collected from the accuser, Crystal Mangum, and her belongings that did not match any of the lacrosse players.

During a North Carolina State Bar disciplinary committee hearing into allegations of unprofessional conduct against Nifong, Meehan testified the district attorney never told him to hide the evidence but never told him to highlight it either.

"Why I didn't do it, it was poor judgment on my partm at the time when I drafted that report," Meehan testified in June.

In court, Nifong said Meehan was eager to be part of the case.

Meehan, as well as the other defendants, have about a month left to respond to the lawsuit. A lawyer representing DNA Security said the company plans to file a motion to dismiss the complaint.