The prosecution of five people in the drug death of actor Matthew Perry ended Wednesday with the sentencing of the personal assistant of the “Friends” star

After a lifetime of sobriety struggles, Matthew Perry spent the last days of his life desperately seeking the ketamine that would ultimately cause his death. The 2 1/2-year investigation and prosecution that followed came to a close Wednesday with the sentencing of his personal assistant Kenneth Iwamasa,

“We trusted Kenny. Kenny’s most important job – by far – was to be my son’s companion and guardian in his fight against addiction,” Perry’s mother, Suzanne Morrison, wrote in a letter to the court, contained in a prosecution finding. “His number one responsibility,” she wrote, was to “ensure that Matthew remained what he wanted to be: drug free.”