WARREN (AP) – Maine prison officials have ruled that a man serving a life sentence in state prison for murder was also responsible for the death of his mother in Florida while he was free on parole.

David Nelson, 53, is one of only 10 prisoners eligible for parole in Maine. He was convicted in 1976 of strangling retired lawyer Raymond Hogan, 66, in a Portland hotel room. That year, the state did away with parole for inmates.

During Thursday’s hearing, officials ruled that Nelson would be considered responsible for the death of his mother, Natalie Babcock, in 1991.

“The board by unanimous decision ruled that David Nelson did unlawfully cause the death of Natalie Babcock,” said Neale Duffet, chairman of the state parole board. “That finding was placed in his prison file.”

Nelson has never been charged in the Florida murder, and prosecutors in Palm Beach County had said they did not intend to. But Maine’s five-member parole board decided evidence was strong enough to hold Nelson accountable for the murder.

Parole remains an option for those convicted of crimes before the law changed, including Nelson. The parole board’s findings will be in Nelson’s file when he comes up for parole again in 2006, Duffett said.

Unlike a criminal jury, which has to reach a unanimous guilty verdict for life imprisonment, the board only needed three members to find Nelson culpable.

Since 2001, the board has released only three people on parole, one who was later returned to prison for new crimes.

In 1991, Babcock filed a car theft charge against Nelson. A day after her body was discovered, he was arrested in Massachusetts driving his mother’s stolen Buick with blood stains on his clothing.

He was charged with drunken driving and imprisoned again for violating parole.

DNA tests showed the blood on Nelson’s clothing matched his mother’s, Duffett said. Two witnesses from Florida testified against Nelson on Thursday.

Florida authorities never charged Nelson with the Babcock murder, though state officials have said they are not sure why.

Nelson’s attorney Eric Morse of Rockland said the state should formally charge his client with a parole violation to see if the Florida evidence meets the standard of proof.

Such a low burden of proof makes defending Nelson against 12-year-old charges nearly impossible, he said.

AP-ES-05-21-04 0216EDT