It’s been one year since California law began allowing terminally-ill residents to get a prescription for medication to end their lives.

Compassion & Choices, the main group behind the law, says it knows of more than 500 people who have gotten a prescription, but it has not tracked how many followed through with ending their lives. The number is based on people who sought the group's help with the process, and its contacts with some hospitals.

The state is required to release a detailed report, but it has not yet done so.

Nearly 500 healthcare facilities and 104 hospice locations "have adopted policies supportive of patient choice and supportive of their doctors and medical professionals who choose to participate in the law," according to Compassion & Choices.

It says roughly 80 percent of the state's private insurance companies cover the cost of lethal medication, including Blue Cross, Blue Shield, Kaiser Permanente, many local health plans and all Medi-Cal plans.

The law has sparked important conversations between patients and their doctors that often lead to patients discovering more palliative care options, says Matt Whitaker, Compassion & Choice's California and Oregon state director.

"The fact that this option is available and that we’re talking about it has opened the door to more open and honest and transparent conversations about all of those different options that exist," he says.

The law has forced California's doctors to confront the difficult question of whether they're comfortable facilitating a patient's death.

Compassion & Choices operates a hotline for doctors seeking more information about the law.

Most of the physicians who call "have had a patient who just recently brought this up and who are saying, 'You know, I’ve thought about this. I want to help this patient and I need some extra information to make that a possibility,'" says Whitaker.

Under the law, two doctors must determine that the patient has less than six months to live, and is capable of deciding to end his or her own life. It has a series of other requirements designed to prevent abuse.

The Catholic Church, disability rights groups and some physicians and medical ethicists oppose the law, arguing that it puts the state on a slippery slope towards legalized euthanasia.

Dr. Aaron Kheriaty, director of UC Irvine’s medical ethics program, objects that the law doesn’t mandate an evaluation by a psychiatrist. He says without that, patients are left without sufficient supports when they're most vulnerable.

"Would they feel differently or would they pursue a different course of action if they felt that they had the familial or the social support or the support from health care professionals that they needed to walk through the process?" he asks.

Kheriaty also questions whether the lack of access to mental health and specialist care might play into a patient’s choice. Access to services vary based on geography and income.

"It’s not so much the folks from Silicon Valley, but the folks in Central Valley that I would be worried about," he says.

The state legislature passed the bill and Gov. Brown signed it into law amid national coverage of a young Californian with terminal brain cancer — Brittany Maynard — who publicized her choice to move to Oregon to legally end her suffering. The Pacific Northwest state has allowed physician-assisted suicide since 1997.

Colorado, Vermont and Washington also have legalized doctor-assisted suicide.