Michael Rivera was convicted in 1987 of the abduction and murder of Staci Jazvac, a Lauderdale Lakes girl who vanished while riding her bike to the store for school supplies.

"We told Michael about the DNA results and he's very happy," said Marty McClain, a death penalty lawyer who represents Rivera.

McClain was optimistic that his client would get a new trial. The hairs were the only significant scientific evidence linking Rivera to Staci's disappearance on Jan. 30, 1986. She was asphyxiated, her body dumped in a Coral Springs field.

Prosecutors focused on two hairs found in a van during their opening and closing statements to the jury, and a crime-lab technician testified that the hairs "could be concluded as being" from Staci's head. The blue van belonged to a friend of Rivera, and Rivera sometimes drove it.

But mitochondrial DNA testing, unavailable at the time of Rivera's trial, proved conclusively this month that there is no match. In the genetic review, the March 11 report from independent tester Mitotyping Technologies excluded Staci as the source of the hairs.

Former Broward County prosecutor Kelly Hancock, who tried Rivera, downplayed the significance of the hairs in a case he considered strong. "It was a very insignificant piece of evidence," said Hancock, who is now in private practice.

Rivera had admitted exposing himself in public, making obscene calls and accosting young girls. He made a series of ominous statements to a polygraph detective, including, "Every time I get into a vehicle, I do something terrible."

A former boss testified that Rivera had made crank calls to her and admitted the murder.

But McClain hopes to add the DNA findings to other evidence not available in Rivera's previous trial, such as the testimony of Mark Peters, who now swears he had the van the night of the murder, not Rivera.

The DNA findings cast doubts on a high-stakes Broward Sheriff's Office case for the second time this week. A federal judge Wednesday overturned the conviction of Timothy Brown for the 1990 slaying of Broward Sheriff's Deputy Patrick Behan, saying that investigators had violated his right to remain silent and that new evidence points strongly to another man as the real killer.

AP-ES-03-21-03 1147EST