SACRAMENTO, Calif.—Physician-assisted suicide will become legal in California under a bill signed into law on Monday by Democratic Governor Jerry Brown.

The law, based on a similar measure in Oregon, allows doctors to prescribe medication to end a patient’s life if two doctors agree the person has only six months to live and is mentally competent.

In a rare statement accompanying the signing notice, Brown, a former Roman Catholic seminarian, said he closely considered arguments on both sides of the controversial measure, which makes California only the fifth U.S. state to legalize assisted suicide for terminally ill patients.

“I do not know what I would do if I were dying in prolonged and excruciating pain,” Brown said. “I am certain, however, that it would be a comfort to be able to consider the options afforded by this bill. And I wouldn’t deny that right to others.”

The new law, which becomes effective Jan. 1, makes it a felony to pressure anyone into requesting or taking assisted suicide drugs. The bill was strongly opposed by some religious groups, including the Roman Catholic Church, as well as advocates for people with disabilities, who said unscrupulous caregivers or relatives could pressure vulnerable patients to take their own lives. Opponents also said the bill would invite insurance companies to take advantage of poor patients by offering to pay for the cost of life-ending drugs but not for the expensive treatments that could save lives.

“There is a deadly mix when you combine our broken healthcare system with assisted suicide, which immediately becomes the cheapest treatment,” said Marilyn Golden, a senior policy analyst at the Disability Rights Education & Defense Fund in Berkeley. “The so-called protections written into the bill really amount to very little.”

But supporters said the measure, introduced after 29-year-old cancer patient Brittany Maynard made headlines by moving from California to Oregon to take her own life last year, would allow people who are terminally ill to die with dignity and greater comfort.

“My daughter did not die in vain,” said Dr. Robert Olvera, an advocate for the measure whose daughter succumbed to leukemia in 2014. “This is the option she wanted to end her suffering.”

As presently written, the law will expire after 10 years unless extended, a compromise with lawmakers who were worried about unintended consequences such as the targeting of the poor, elderly and disabled.