Kenneth Iwamasa, Matthew Perry’s live-in assistant, is set to be sentenced Wednesday for repeatedly injecting ketamine in the weeks before Perry died in October 2023, pleas and court filings describe. Prosecutors say Iwamasa ignored warning signs, destroyed ev
On Wednesday, Kenneth Iwamasa will stand before a judge facing sentencing in the ketamine case tied to Matthew Perry’s death in 2023—an end point for a crime prosecutors describe as months of betrayal inside a home, not just a single fatal overdose.
Iwamasa is one of five people charged and convicted in what prosecutors called a conspiracy to illegally distribute ketamine to Perry. He pleaded guilty in August 2024 to one count of conspiracy to distribute ketamine resulting in death. Prosecutors say he was the final defendant to be sentenced in the case.
In their sentencing memorandum ahead of the hearing. prosecutors wrote that when Iwamasa was hired as Perry’s live-in personal assistant. he was acutely aware that Perry had suffered from drug addiction for most of his life. But instead of helping Perry maintain sobriety. prosecutors said Iwamasa became an enabler and drug supplier—injecting Perry repeatedly in the weeks before the actor’s death.
The fatal details—according to prosecutors—start with repeated warnings. Prosecutors said Iwamasa found Perry unconscious inside his home at least two times in October 2023. They also said he saw Perry “freeze up” after a large injection. Yet, they wrote, “ignoring these warnings,” he continued to inject Perry with illicit ketamine.
In the days leading up to Perry’s death. prosecutors said Iwamasa injected him with “significant quantities of ketamine.” On the day Perry fatally overdosed. prosecutors said Iwamasa injected him with two doses before Perry asked him to prepare the jacuzzi and to “shoot me up a big one.” Prosecutors wrote that soon after administering the third dose. Iwamasa left to run errands for Perry. When he returned, prosecutors said he found Perry dead, face down in the jacuzzi.
Prosecutors also allege that the wrongdoing did not stop after the overdose. They wrote that following Perry’s death. Iwamasa continued his wrongdoing by destroying evidence and taking other steps to cover his tracks and obstruct justice. Prosecutors said he cleaned up ketamine bottles and syringes from the scene. and omitted ketamine from the list of Perry’s medications while being questioned by officers after calling 911.
Iwamasa has asked for 41 months—nearly 3 1/2 years—in prison. Prosecutors said he provided “significant cooperation” in the government’s investigation, including information on other defendants.
Defense attorneys, in response to the government’s sentencing memo, argued that Iwamasa did not abuse his “trusted position.” They said he was an employee and “acted at all relevant times at the victim’s direction rather than pursuant to his own discretion.”
In their filing, defense attorneys pushed back on prosecutors’ framing of the employment relationship as a defining factor. They wrote: “Perhaps Defendant’s employment relationship with the victim enabled him to more readily participate in the conspiracy to distribute drugs to the victim than a man on the street. but it should be noted that a number of proverbial men on the street did in fact participate in the same conspiracy.” They added that “multiple third parties were involved who did not share the same relationship with the victim. ” and argued that “fact alone should overcome the inference that it was Defendant’s particular relationship with the victim that facilitated the crime.”.
Prosecutors said Iwamasa worked with two doctors to obtain ketamine for Perry before turning to two dealers to obtain dozens of vials of ketamine, including the doses that killed the actor.
They also said Iwamasa had known Perry since around 1992, before becoming Perry’s live-in assistant in 2022 for $150,000 a year. Prosecutors said his responsibilities included those related to Perry’s medical care.
A victim impact statement filed ahead of sentencing carried a harsher tone. Perry’s mother wrote that the family was relieved when Perry took on an assistant whom she said understood the actor’s battles with drug addiction, and that they all trusted Iwamasa.
“Kenny’s most important job — by far — was to be my son’s companion and guardian in his fight against addiction. His number one responsibility — ensure that Matthew remained what he wanted to be: drug free,” she wrote. “Kenny knew. should he feel unduly pressured. that with one phone call to any number of the people in Matthew’s orbit. reinforcements would be on the way. and his job would be safe.”.
“But instead of protecting Matthew, he aided and abetted illegal drug taking, arranged for one source of supply, then another. Shot the drugs into Matthew’s body though he was not in the least qualified,” she continued. “He did it even though he could see, anyone could have seen, it was so obviously dangerous. And he did it again and again.”.
Iwamasa is the fifth and final defendant in the case to be sentenced in the scheme to illegally distribute ketamine to Perry.
By the time of this Wednesday hearing, much of the lineup is already settled in court. Prosecutors said Jasveen Sangha—reportedly known as the “Ketamine Queen”—worked with Erik Fleming to distribute 51 vials of her ketamine to Iwamasa. including the doses that killed Perry. Sangha was sentenced last month to 15 years in prison. She pleaded guilty last year to one count of maintaining a drug-involved premises. three counts of distribution of ketamine. and one count of distribution of ketamine resulting in death or serious bodily injury.
Fleming was sentenced last month to two years in prison after pleading guilty to one count of conspiracy to distribute ketamine and one count of distribution of ketamine resulting in death.
The two doctors convicted in the case were sentenced last year. Mark Chavez—who once ran a ketamine clinic—admitted to selling fraudulently obtained ketamine to Salvador Plasencia, who briefly treated Perry, and then sold it to the actor in the weeks before his death.
Chavez pleaded guilty to one count of conspiracy to distribute ketamine and was sentenced to eight months of home confinement in December 2025. Plasencia pleaded guilty to four counts of distribution of ketamine and was sentenced to 30 months in prison in December 2025.
With Iwamasa still facing sentencing—after pleading guilty to conspiracy to distribute ketamine resulting in death and with prosecutors seeking up to 15 years—Wednesday’s hearing will land where the case has been building all along: inside a home. around a man struggling with addiction. and on the question of what “care” became when the person closest to him chose to supply the drugs instead.
Matthew Perry Kenneth Iwamasa ketamine sentencing live-in assistant addiction Friends actor Jasveen Sangha Erik Fleming Mark Chavez Salvador Plasencia