Another doctor pleads guilty following Matthew Perry's drug overdose death

LOS ANGELES – One of two doctors charged in the investigation into Matthew Perry's death is expected to plead guilty Wednesday in federal court in Los Angeles to conspiracy to distribute the surgical anesthetic ketamine.

Dr. Mark Chavez, 54, of San Diego, signed a plea agreement with prosecutors in August and would be the third person to plead guilty after the incident Friends Star's fatal overdose last year.

Read more: Matthew Perry wanted to be remembered for helping others recover from addiction

Prosecutors offered Chavez and two others lesser charges in exchange for their cooperation as they pursue two targets they believe are more responsible for the overdose death: another doctor and an alleged dealer they say is known as the “ketamine queen.” Los Angeles was known.

Chavez is free on bail after surrendering his passport and medical license, among other things.

His attorney, Matthew Binninger, said after Chavez's first court appearance on August 30 that he was “incredibly remorseful” and was trying to “do everything in his power to right the wrong that happened here.”

Also cooperating with federal prosecutors are Perry's assistant, who admitted to helping him obtain and inject ketamine, and an acquaintance of Perry's who admitted to acting as a drug courier and middleman.

The three are supporting the prosecutors in the prosecution of Dr. Salvador Plasencia, who is accused of illegally selling ketamine to Perry the month before his death, and Jasveen Sangha, a woman who authorities say sold the actor the fatal dose of ketamine. Both have pleaded not guilty and are awaiting trial.

Chavez admitted in his plea agreement that he obtained ketamine from his previous clinic and from a wholesaler where he filled a fraudulent prescription.

After pleading guilty, he could face up to ten years in prison if convicted.

Perry was found dead by his assistant on October 28th. The coroner concluded that ketamine was the primary cause of death. The actor had used the drug through his family doctor as part of a legal but unlicensed treatment for depression, which is becoming increasingly common.

Perry began taking more ketamine than his doctor wanted to give him. About a month before the actor's death, he found Plasencia, who in turn asked Chavez to get the drug for him.

“I wonder how much this idiot will pay,” Plasencia wrote to Chavez. The two met the same day in Costa Mesa, halfway between Los Angeles and San Diego, and exchanged at least four vials of ketamine.

After selling the drugs to Perry for $4,500, Plasencia asked Chavez if he could continue to supply them so they could become Perry's “go-to guy.”

Perry struggled with addiction for years, dating back to his time Friendswhen he became one of the biggest stars of his generation as Chandler Bing. From 1994 to 2004, he starred alongside Jennifer Aniston, Courteney Cox, Lisa Kudrow, Matt LeBlanc and David Schwimmer on NBC's mega-hit sitcom for ten seasons.