A Virginia man who served 18 years in prison for a crime that even the prosecutor and detective who put him there don't think he committed walked free on parole yesterday and immediately vowed to fight to clear his name.

"I'll go to my grave trying," Michael McAlister said after his release from Lunenburg Correctional Center in south-central Virginia. "I didn't do it, and they know I didn't do it."

McAlister's attorney, Michael Morchower, said he plans to file another petition for clemency with Gov. Mark R. Warner (D) in an effort to get the 1986 attempted-rape conviction expunged from McAlister's record. Warner rejected an earlier petition, even though the detective and prosecutor signed affidavits saying they believed the victim had misidentified McAlister.

"We're cautiously optimistic," said Morchower, who has hired a private investigator to try to dig up new evidence and locate the victim. "I'm confident we can conclusively exonerate him."

For McAlister, 48, the bitterness of losing 18 years was overwhelmed yesterday by a profound joy. He left his cell at 7:45 a.m. and was taken to the property room, where he abandoned his prison clothes and even his television, keeping only books. Then he walked through several gates to the main prison building, where his mother, Rebecca, and six other family members -- including two who had flown in from Texas -- were waiting.

"I headed straight for my mother. This is her day. She's still crying," McAlister said in a telephone interview from his sister's home near Richmond, where the family had gathered for a cookout. "The whole thing is surreal. It hasn't really sunk in yet. I'm just kind of walking around in a daze, looking at things."

The most emotional moment came when McAlister spoke by telephone with his two daughters, both of whom live in Florida. His younger daughter, Rebecca, was 4 when he went to prison and remembers him only as an inmate. "It's been a long time since I got choked up about anything, but I did when I talked to them," McAlister said.

His other daughter, Rachelle, who was 7 when McAlister went away, said she will be thrilled to have her father attend her wedding in May. "It's been a long time coming," she said. "I went a long time without a dad."

Warner's press secretary, Ellen Qualls, would not comment on McAlister's case. When requests for clemency are filed, she said, they are sent to the Virginia Parole Board for an investigation and recommendation, then back to the governor's office for a decision.

McAlister, a carpenter, was convicted in 1986 of being the masked attacker who tried to rape a young mother as she was doing laundry at a Richmond apartment complex. She was abducted by a man wearing a stocking over his head who forced her outside at knifepoint and ordered her to undress. She struggled and escaped.

At the trial, Joseph D. Morrissey, then the Richmond commonwealth's attorney, told the judge that McAlister was guilty of attempted rape and abduction "pure and simple." The judge sentenced McAllister to 50 years in prison, with 15 suspended.

But new evidence later emerged about another possible suspect. Morrissey and former detective Charles M. Martin signed sworn affidavits questioning McAlister's guilt.

"I am now convinced that Mr. McAlister did not commit the crimes for which he is incarcerated and that he was simply misidentified by the victim," Martin wrote. He and Morrissey testified on McAlister's behalf before the Parole Board. Neither had testified on a convict's behalf before.

But the board repeatedly refused to release McAlister, and Warner rejected the clemency petition that was filed in 2002. Other efforts to exonerate McAlister went nowhere.

Under Virginia law at the time, courts could not consider new evidence of innocence if it was brought forward more than 21 days after sentencing. In 2001, legislators changed the law to allow DNA evidence to be introduced at any time, but there was no such evidence in McAlister's case.

The General Assembly recently expanded Virginia law to allow courts to consider non-biological evidence of innocence long after a conviction. But that law took effect July 1, too late to help McAlister. He had been sentenced before Virginia abolished parole in the mid-1990s and reached his mandatory parole date yesterday.

As he contemplated all he has been through, McAlister vowed to move forward. He said he has lined up a telemarketing job and will work with his attorney to clear his name.

"I am overwhelmed right now," he said. "I am angry, but it's time to start moving past that. I just want to get on with my life."

Michael McAlister, released on parole yesterday after 18 years in prison, walks with his sister Denise Haas, left, and mother, Rebecca. The prosecutor and detective in his case have said McAlister was probably misidentified by the victim. A faded mug shot of McAlister from court files in the Richmond attempted-rape case.Attorney Michael Morchower listens while his client Michael McAlister talks on the phone after his release from prison on parole. "I'm confident we can conclusively exonerate him," Morchower said.