A federal judge sentenced Kenneth Iwamasa, Matthew Perry’s former live-in assistant, to more than three years in prison after finding he repeatedly injected the actor with ketamine, including the fatal dose that led to Perry’s death in October 2023.
In the aftermath of Matthew Perry’s death, one detail kept resurfacing in court: the person closest to him said he was trying to help—then kept administering ketamine anyway.
On Wednesday. a federal judge sentenced Kenneth Iwamasa. the actor’s former live-in assistant. to more than three years in prison after concluding that he repeatedly injected Perry with ketamine. including the fatal dose. The sentence follows Iwamasa’s guilty plea in August 2024 to conspiracy to distribute ketamine causing death. The case made him the last of five people charged in connection with Perry’s death to be sentenced.
U.S. District Judge Sherilyn Peace Garnett ordered Iwamasa, 61, to self-surrender by July 17 and imposed a $10,000 fine. In delivering the sentence. Garnett told Iwamasa. “You were privy to his struggle with addiction.” She added that his conduct was “reckless. not just on the day of his death but leading up to his death.”.
Prosecutors asked for a 41-month sentence—what Garnett ultimately imposed. Iwamasa’s defense attorneys had urged far less time, asking for six months of incarceration and six months of home confinement.
During an hours-long sentencing hearing, Assistant U.S. Atty. Ian Yanniello said Iwamasa obtained more than 70 vials of ketamine for Perry in a month. Yanniello framed the case as a failure of trust.
“This case is about a breach of trust. … Mr. Perry wanted to overcome his demons and live a sober life,” Yanniello said, calling Iwamasa “a drug supplier and enabler.”
Iwamasa’s attorney, Alan Eisner, pushed back on that characterization. He told the court that Perry “was not a bystander here” and argued that Perry was “not blameless in the events that led to his own death.” Eisner also said Iwamasa “didn’t have the spine to say no to his boss.”
Garnett responded with a direct refusal to accept that framing. “Unwilling — not unable,” she said, after earlier comments on whether Iwamasa could have refused.
Eisner continued, saying, “He could have said no and shame on him for not saying no,” and arguing Iwamasa “didn’t have the strength of character to do that.”
As the hearing unfolded, people tied to Perry’s life challenged Iwamasa’s account from the other direction—portraying him as someone exerting control even as Perry fought addiction.
Lisa Ferguson, Perry’s longtime business manager and the appointed executor of his estate, scoffed at the defense suggestion that Iwamasa lacked power. She accused him of wanting “control over Matthew and everything he owns.”
Ferguson told the court that Perry, “was terrified of dying. He wanted to live.” Turning to Iwamasa, she said, “What you are,” is “the monster who killed him.”
“Matthew deserved to live,” Ferguson added. “You don’t.”
Perry’s mother, Suzanne Morrison, had also written to the judge ahead of sentencing. In her letter. Morrison said one of Iwamasa’s responsibilities “was to be my son’s companion and guardian in his fight against addiction.” She wrote that after Perry’s death. Iwamasa insisted on speaking at the funeral and clung to the family “as if he was somehow the good guy who tried to save Matthew.” Morrison accused him of threatening legal action “to pry a settlement from workman’s comp.”.
“We trusted a man without a conscience, and my son paid the price,” Morrison wrote.
Before sentencing, Iwamasa pleaded guilty in August 2024 to conspiracy to distribute ketamine causing death. Prosecutors said that while he was not trained medically, he injected Perry multiple times.
According to court records, Iwamasa had been known to Perry since around 1992 and became his live-in assistant in 2022. Prosecutors said his responsibilities included coordinating medical appointments and helping ensure Perry took medication that he was lawfully prescribed.
At the time of the guilty plea, Iwamasa had previously made $150,000 a year working for Perry, and he admitted to repeatedly injecting the actor, who was 54, with ketamine without medical training— including multiple injections on Oct. 28, 2023, the day Perry died.
Perry was found dead in the hot tub of his Pacific Palisades home from acute effects of the drug.
Prosecutors said that at least as early as September 2023, Perry requested Iwamasa’s help procuring illegal drugs. They also said that throughout October 2023. Iwamasa repeatedly injected Perry “with doses of ketamine without proper medical training or the equipment necessary to ensure the drug was being safely administered.” The government said he saw “clear warning signs that Mr. Perry was in danger.”.
In October, prosecutors said Iwamasa found Perry unconscious in his home at least twice. They also said Perry “freeze[d] up,” unable to speak after a large ketamine injection. Still, prosecutors said that between Oct. 24 and Oct. 27, he injected Perry with six to eight shots per day.
On the day of Perry’s death, court records state that Iwamasa—at Perry’s direction—shot him with ketamine in the morning and again while watching a movie around midday. Less than an hour later, prosecutors said Perry asked him to prepare the hot tub and “shoot me up with a big one.”
Under the plea agreement, Iwamasa filled a syringe with ketamine and administered it to Perry while the actor was in or near the tub. Soon after, he left to run errands for Perry. When he returned, he found Perry’s body.
Prosecutors said that when questioned by police, Iwamasa concealed the injections he’d administered. They said he also took steps to remove and destroy evidence related to Perry’s ketamine use in the days leading up to his death.
Even so, prosecutors said Iwamasa later provided “significant and credible information related to the drug conspiracy,” and they noted that he was the first defendant to cooperate against others.
The sentencing hearing also touched on the broader criminal cases connected to Perry’s death. This month. a judge sentenced Erik Fleming. a former producer and drug counselor. to two years in prison for distributing the ketamine that killed Perry. Jasveen Sangha, known as the “Ketamine Queen,” was sentenced last month to 15 years in prison. Salvador Plasencia. a former physician who supplied ketamine to Perry in the weeks leading up to his death. received 30 months in prison. Mark Chavez. another former doctor who played a role in providing the actor ketamine. was sentenced to eight months of house arrest.
After the sentencing hearing, Eisner and Dmitry Gorin said Iwamasa “cared tremendously for Mr. Perry and continues to feel deep remorse over what happened.” They said Iwamasa “worked in the industry for decades. had never been in trouble with the law. and was respected by friends and family.” They added that while they were disappointed in the sentence. Iwamasa “has grown from this tragedy and looks forward to pursuing new goals and achieving positive accomplishments in his life.”.
In his own remarks to the court. Iwamasa turned toward Perry’s family and loved ones in the front row and offered an apology. “I’m sorry to have done illegal acts that I will forever regret. I’ll take that to my grave,” he said. “I’m horribly, horribly sorry. And I offer my condolences to you.” He later clasped his hands as if in prayer.
In Morrison’s letter, she thanked investigators and the judge for their “calm and careful deliberation.” She ended with a rejection of the idea that the case could truly bring comfort.
“[C]losure. Such a thing doesn’t exist,” Morrison wrote. “Ask any mother whose child has been torn away so mercilessly. Nothing takes this pain away, nor will it, I am sure, for as long as I live.”
Matthew Perry Kenneth Iwamasa ketamine Pacific Palisades federal sentencing Sherilyn Peace Garnett U.S. District Court
So he just injected him? wild.
I don’t get how someone could “help” and then keep doing it. Like at that point it’s not treatment it’s just… poisoning. Three years seems kinda low for something that killed him though.
Wait, I thought the ketamine was supposed to be legal/doctor stuff? If it was “prescribed” then why is he the one going away? Also the judge said “privy to his struggle” like that makes it less bad??
This whole thing makes me think no one was watching that apartment. Like how did the assistant even have ketamine around like that, and how many chances did he get before the fatal dose? I swear every time I hear about this case it’s a new twist, and then it’s always “he thought he was helping” smh. Just sad.