A Santa Rosa man charged with stabbing his mother to death with a pair of scissors and a dagger pleaded guilty Thursday to first-degree murder.

Christopher Lavis, 42, was awaiting trial in the 2008 slaying of Connie LaSalle, 63, in the Santa Rosa condominium they shared.

Prosecutors agreed to drop a torture allegation in exchange for his guilty plea but a murder conviction combined with weapons enhancements could still put him behind bars for life.

Deputy District Attorney Traci Carrillo said given the fact that two judges had already struggled with the torture charge — which could have brought death or life without parole on conviction — the plea agreement seemed appropriate.

"It's certainly forseeable that a jury would struggle," Carrillo said. "This really gives a sense of finality to the family of the victim and next of kin."

Judge Lawrence Antolini set sentencing for Nov. 30. Prosecutors said they would not seek the death penalty.

Lavis was accused of stabbing his mother 45 times during an argument on Sept. 10, 2008. Detectives said the often-homeless man covered her body with blankets and remained in the apartment for 10 days ordering pizza and emptying her refrigerator.

After his arrest in San Francisco, Lavis admitted the killing, explaining he snapped when his mother tried to kick him out. He began stabbing her with kitchen shears and used a Roman gladius for the final blow, he said.

"And I just ... I couldn't take it anymore," he said in court papers. "So, and that's when I did it."

Carrillo contended that the number of shallow wounds on LaSalle's body were evidence of torture.

But defense attorney Amy Chapman argued he never intended to make his mother suffer. Chapman said that when Lavis realized his mother was in pain he pulled the dagger for a quick death.

Two judges, Lawrence Antolini and Ken Gnoss, pondered motions to drop the torture allegation but concluded it was warranted.

Under Lavis' guilty plea, he will serve 26 years to life in prison before becoming eligible for parole.

Also, he agreed to waive all appeal rights, Carrillo said.