In the years Mr. Kevorkian spent in prison, little has changed legally in this realm across the country. Oregon remains the only state with a law in which a terminally ill patient can ask a doctor to prescribe a lethal amount of medication under certain circumstances. Since 1998, 292 people have died under the terms of Oregon’s Death With Dignity Act.

Image Jack Kevorkian, center, with his lawyer Mayer Morganroth, far right, as he was released from prison on Friday in Coldwater, Mich. Credit... Carlos Osorio/European Pressphoto

Other states, including Vermont, have rejected such proposals, and national advocates for assisted suicide said they would be watching California’s bill next week with particular concern.

“If it doesn’t pass there, that will be a pretty good sign to us that no legislative body will pass it,” said Barbara Lee, the president of Compassion & Choices, a group based in Denver and Portland that supports assisted suicide.

Mr. Kevorkian was tried four times in the deaths of ill people before being convicted in 1999 of giving a fatal injection to Thomas Youk, a 52-year-old man who had Lou Gehrig’s disease. He was sentenced to 10 to 25 years. The main evidence against him was a tape showing the injection that Mr. Kevorkian had taken to “60 Minutes,” the CBS News program that broadcast it at the time along with an interview in which Mr. Kevorkian challenged the law enforcement authorities to try him.

Outside the prison on Friday, Mr. Kevorkian briefly embraced Mike Wallace, the “60 Minutes” correspondent who taped a new interview with him on Friday. It is to be broadcast on Sunday evening. Mr. Kevorkian, the same gaunt, white-haired figure familiar to many, smiled and quietly told reporters that leaving prison was “one of the high points of life.” His lawyers have said he is ill, suffering from hepatitis C. He will live with friends in Michigan.

Russ Marlan, a spokesman for the state’s Department of Corrections, said the conditions of Mr. Kevorkian’s parole did not preclude his speaking broadly in support of the notion of assisted suicide, but barred him from helping anyone directly.

Mr. Kevorkian’s friends welcomed his return, calling him a caring leader who had aided the wishes of the terminally ill and who, in return, had been grossly abused by the legal system. They had little patience with national advocates now distancing themselves from Mr. Kevorkian.