One of two doctors charged in the investigation of the death of Matthew Perry is expected to plead guilty on Wednesday in a federal court in Los Angeles to conspiring 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 in the aftermath of the 'Friends' star's fatal overdose last year.

ADVERTISEMENT Prosecutors offered lesser charges to Chavez and two others in exchange for their cooperation as they go after two targets they deem more responsible for the overdose death: another doctor and an alleged dealer that they say was known as ' ' of Los Angeles. Chavez is free on bond after turning over his passport and surrendering his medical license, among other conditions. His lawyer Matthew Binninger said after Chavez's first court appearance on August 30 that he is 'incredibly remorseful' and is 'trying to do everything in his power to right the wrong that happened here'.

Also working with federal prosecutors are Perry's assistant, who admitted to helping him obtain and inject ketamine, and a Perry acquaintance, who admitted to acting as a drug messenger and middleman. The three are helping prosecutors in their prosecution of Dr. Salvador Plasencia, charged with illegally selling ketamine to Perry in the month before his death, and Jasveen Sangha, a woman who authorities say sold the actor the lethal dose of ketamine.

Both have pleaded not guilty and are .