KANSAS CITY, Missouri — A former trash company supervisor was convicted yesterday of murdering six women whose strangled bodies were found scattered around the area two decades ago.Under a deal with prosecutors, the only possible sentence for Lorenzo Gilyard, 56, was life in prison. He was acquitted of a seventh murder.

Police were testing genetic evidence in old, unsolved cases in 2004 when they linked Gilyard’s DNA to the deaths of a dozen women, all but one of whom were prostitutes. A 13th murder count was added last year.

Prosecutors pursued charges in what they considered the seven strongest cases, dropping the other six as the trial began earlier this month.

Prosecutors agreed in January not seek the death penalty against Gilyard, as long as defense attorneys allowed a trial before a judge without a jury.

In his ruling, Judge John O’Malley called the cases “obscene insults to our sense of justice, security and freedom.”

Relatives and friends of the victims hugged and cried after the verdict.

Defense attorney Susan Elliott declined to comment.

The bodies were found in sexually compromising positions around the Kansas City area in 1986 and 1987.

Prosecutors said Gilyard had sex with the women just before they died. Semen or seminal fluid was found on the six victims whose cases brought convictions.

They are Catherine M. Barry, 34, the only victim not known to have worked as a prostitute; Naomi Kelly, 23; Ann Barnes, 36; Kellie A. Ford, 20; Sheila Ingold, 36; and Carmeline Hibbs, 30.

The judge acquitted Gilyard of killing Angela Mayhew, 19, whose body was the only one that didn’t contain semen or provide other DNA evidence.

O’Malley said that in the Mayhew case, prosecutors had left him only with suspicions of guilt, not convincing proof.

Gilyard had a history of scrapes with the law and had served time for crimes including child molestation. From 1969 to 1974, he was a suspect in five rape cases, though he was never convicted, court records show.

He was linked to the 1980s murders by a blood sample he gave in 1987, when he was a suspect in one of the deaths.

Until his April 2004 arrest, Gilyard had lived with his wife of about a decade in a modest home at the end of a quiet dead-end street. His wife divorced him after his arrest.

Sentencing was set for April 13.