With less than a month before condemned murderer Terrance Williams is scheduled to die by lethal injection, his advocates on Thursday chose an option not used in a half-century: a plea for clemency from the governor.

Lawyers for Williams, 46, formerly of Philadelphia, filed the petition asking Gov. Corbett and the state Board of Pardons to stop Williams' Oct. 3 execution and commute his sentence to life in prison without parole.

A broad-based group of lawyers and former judges, child advocates, and religious figures - including the widow of the man Williams killed in 1984 - urged that his life be spared for a crime committed three months after he turned 18, the minimum age for someone to be sentenced to death in the United States.

Moreover, the petition says, five members of the Philadelphia Common Pleas Court jury that condemned Williams for the murder of Amos Norwood have said they would have opted for life in prison had they heard mitigating evidence about Williams' horrific childhood of sexual abuse by a neighbor, a teacher, and Norwood himself.

"The evidence of abuse in this case is clear," reads a letter of support signed by 26 child advocates and experts in sexual abuse. "There can be no doubt that Terry was repeatedly and violently abused and exploited as a child and teenager by manipulative older men.

"Terry's acts of violence have, alas, an explanation of the worst sort: enveloped by anger and self-hatred, Terry lashed out and killed two of the men who sexually abused him and caused him so much pain."

The five-member Board of Pardons, chaired by Lt. Gov. Jim Cawley, set a public hearing for Sept. 17 in Harrisburg.

Under state law, the board must be unanimous if it recommends that the governor spare Williams' life. The recommendation is not binding on Corbett, who set the process in motion Aug. 9 by signing Williams' death warrant.

Williams' lawyer Shawn Nolan, assistant chief of the death-penalty unit at the Federal Defender's Office in Philadelphia, said he also had sought an emergency stay of execution in Philadelphia Common Pleas Court that will be heard Monday by Judge M. Teresa Sarmina.

If Williams' execution takes place, it would be the first in 13 years. Only three people have been executed since Pennsylvania reenacted capital punishment in 1978 - two in 1995, the last in 1999 - and only because all three ended appeals and asked for death.

Before 1978, the last involuntary execution in Pennsylvania was in 1962 when Elmo Smith of Norristown died in the electric chair for the rape-murder of a 17-year-old Montgomery County girl.

Lending support to Williams' clemency petition are 22 former prosecutors and judges, 34 law professors, 40 mental-health professionals, and more than 36 religious leaders, including Archbishop Charles J. Chaput, leader of the Roman Catholic Archdiocese of Philadelphia.

But Williams' strongest asset may be an extraordinary affidavit by his victim's widow. Mamie Norwood, 75, describes a personal transformation from anger and resentment to forgiveness.

At first, Norwood wrote, her husband's murder was "unbearable for me. [But] several years ago, after much prayer and self-reflection, I found the strength and courage to forgive Terry Williams.

"I do not wish to see Terry Williams executed," Norwood wrote. "His execution would go against my Christian faith and my belief system. He is worthy of forgiveness, and I am at peace with my decision to forgive him and have been for many years. I wish to see his life spared."

Through a representative, Norwood declined to be interviewed, saying, "I'd like to rely on my affidavit."

The clemency petition could be Williams' last hope of escaping execution; his lawyers say he has exhausted all appeals. It's a long shot because of the rule that the Board of Pardons be unanimous and because its recommendation is not binding.

Nolan, however, said that the last 50 years has seen major strides in the law and punishment of juvenile and young offenders. Brain research has documented the immaturity of teen thinking and decision-making and the lasting impact of childhood sexual abuse.

"Look what we've seen in the last year in Pennsylvania," said Nolan, referring to the pedophilia scandals involving former Penn State assistant football coach Jerry Sandusky and priests in the Archdiocese of Philadelphia.

Since 2009, the clemency petition says, five governors in four states, including Delaware, have commuted death sentences because of mitigating evidence.

Williams was a Cheyney University freshman when he was arrested in the murder of Norwood, who was last seen leaving his Mount Airy home June 11, 1984, to do volunteer work at St. Luke's Episcopal Church in Germantown.

Four days later, a boy walking his dog found Norwood's charred body propped against a gravestone in Ivy Hill Cemetery in West Oak Lane. Norwood had been beaten to death with a tire iron.

A month later, police charged Marc Draper, 18, son of a police Civil Affairs Unit officer. Draper, in turn, implicated Williams in the killing he said began as a robbery.

Draper also told police that Williams admitted to him that on Jan. 26, 1984, he had stabbed to death Herbert Hamilton, 50, after Hamilton made sexual advances.

Hamilton's nude body, beaten and stabbed, was found in his West Philadelphia apartment.

The charges stunned those who knew Williams as a young man who overcame an abusive family to excel as a Germantown High School quarterback and go on to college.

None of that information - Williams' physical abuse by his mother and stepfather, and childhood sexual abuse by a neighbor, a teacher, and Norwood - was presented to the jury that condemned him to death in February 1986.

Draper became the key prosecution witness against Williams in both killings.

Williams was convicted of third-degree murder in Hamilton's death in February 1985 after the jury believed his self-defense claim and evidence of Hamilton's homosexuality.

A year later, Williams was convicted of first-degree murder in Norwood's killing and sentenced to death.

Draper pleaded guilty to second-degree murder in Norwood's death and was sentenced to life.

Now 46, Draper is in the state prison in Frackville, Schuylkill County. He has recanted his earlier claim that Norwood's murder was motivated by robbery. Draper now says that Williams was angry about his sexual abuse by Norwood, "became enraged, and was kind of losing his mind right before Norwood was killed."

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