A man who was convicted of killing a police officer and who walked away from a D.C. halfway house last year and apparently lived incognito in Woodbridge until his arrest Saturday on charges of beating his wife was being held yesterday without bail in the Prince William County jail.

Olen Lebby, 42, has waived extradition on a fugitive warrant from the D.C. Department of Corrections for his escape last Aug. 12, police said. He will be returned to the District to face unlawful flight charges after his trial on the misdemeanor assault charge. Trial has been set for Monday.

Lebby was arrested about 9:10 p.m. Saturday at a Westminster Lane apartment after police responded to a call from his wife, Alfreida, who alleged that he had struck and attempted to choke her after she refused to lend him her car, said Sgt. Mike Hinderliter.

Alfreida Lebby told police her husband was wanted for running away from a halfway house in Washington, Hinderliter said. "She told us he had killed a police officer," he said.

Lebby was convicted of second-degree murder in 1975 in the shooting death of D.C. Officer Vernon N. Johnson, who died from a gunshot wound to the neck he received during a gun battle with Lebby near 13th and F streets NW after the men argued. Lebby was shot in the chest.

He was arrested in Michigan in 1974 on an armed robbery charge and was convicted of assault with a dangerous weapon and carrying a weapon without a license in the District before shooting Johnson, police said.

At his trial, Lebby told a jury he made his living as an enforcer, employed by 14th Street pimps to maintain peace between their prostitutes and their customers by using a baseball bat.

In an interview with The Washington Post in 1983, Lebby, who spent two years in the Marine Corps, said his problems with the law began after he returned from the Vietnam War in 1970. "Killing ain't so bad once you get used to it," he said. "That's what the government trained me to do; that's the job that I do best."

Lebby served nine years of a nine-to-27-year sentence for the murder and was paroled in November 1984. He was jailed again briefly in May 1986 after violating parole by smoking marijuana, officials said.

Lebby, who characterized himself as "a family man" to parole officials, violated parole a second time in 1988 -- this time for failing to tell his parole officer where he was -- and was jailed for eight months until he was transferred from Lorton to a D.C. halfway house, police said.

He walked away last year on a one-day pass to visit his wife in Woodbridge.

D.C. corrections warrant investigator Tommy Lawrence said he traveled to Prince William County several times in 1989 to look for Lebby but had been unable to find him.

Lawrence said he had not contacted police to inform them that Lebby might be in the vicinity. "You don't want to spook this guy," by coming into the neighborhood with a full entourage of police, he said.

Lawrence said Lebby's name was listed on District and federal computerized fugitive warrant systems. Pat Wheeler, D.C. Department of Corrections spokeswoman, refused yesterday to let Lawrence say when he last came to Prince William looking for Lebby. "He'd have to go through his whole notebook to know that," she said.

Saturday, Lebby was carrying a false identification card with the name of Robby Lebby, and a false date of birth, Hinderliter said.

He also carried pay stubs indicating he had worked in Prince William for almost a year, but police said they did not look to see the name of his employer.

Lebby told police he had been living with his wife, but she denied that, Hinderliter said.