Golden added that many people who initially received terminal diagnoses have “lived full lives [for] years or even decades” longer than expected.

Disability-rights advocates have fought against bills and referendums in Massachusetts, Colorado, Connecticut, and elsewhere that would have allowed doctors to prescribe lethal medication. They have met with legislators, participated in forums, conducted letter-writing campaigns, and submitted newspaper opinion pieces.

“We have had success after success in stopping these bills,” said John Kelly with Not Dead Yet, a grassroots group of advocates opposed to physician-assisted suicide. The coalition was less organized when laws passed in Washington, Oregon, and Vermont, Kelly said. Now, he said they are determined to defeat any bill, including the one in California.

Allowing doctors to prescribe such medication would “open the floodgates” to people taking their lives under the mistaken impression that they are imminently dying or because they think they are a burden on their families, he said.

The proposed California legislation, Senate Bill 128, was prompted by the highly publicized death of Brittany Maynard, a young Bay Area woman with terminal brain cancer who moved to Oregon so she could get a lethal prescription. She took the medication and died in November.

The End of Life Option Act, introduced by Democratic state Senators Lois Wolk and Bill Monning, would allow patients to get fatal prescriptions if they are mentally competent and have six months or less to live. Patients would have to make one written and two oral requests 15 days apart.

Disability rights advocates say there aren’t enough safeguards in the bill. In a letter to Wolk late last month, Deborah Doctor, a legislative advocate for Disability Rights California, wrote that disabled people are vulnerable to abuse and could be coerced by family members not acting in the patients’ best interests. Relatives, she said, could put pressure on people to take life-ending medication.

“Everyone is not Brittany Maynard,” Doctor said in an interview, noting that the young woman’s family supported what she wanted. “Our responsibility is to think of people who are the most vulnerable to coercion, abuse, and pressure.”

Doctor also worries that in other cases, physicians may simply be wrong about how long someone has to live. Insurance companies also might overrule treatment for people with disabilities because of the cost of care.

Supporters of the bill say it has many protections built in. For example, they say, people wouldn’t qualify based solely on having a disability. The bill also wouldn’t allow medication to be prescribed if the person were suffering from a mental disorder that impaired judgment.

In addition, physicians would have to attest that the patient’s request didn’t result from undue influence from someone else. And patients would have the final say—they must administer the medications to themselves.