A judge has ruled California’s law allowing terminally ill people to end their lives was passed legitimately during a special session of the Legislature, dampening a long-running criticism by opponents who sued over the measure.

A Riverside County Superior Court judge also found this week that the doctors who sued presently don’t have the right to do so to try to block the law, Compassion & Choices, a group that supports the measure, said in a statement on Friday.

The decision is the latest in a long-running battle over the 2016 law that allows adults in California to obtain a prescription for life-ending drugs if a doctor finds they have six months or less to live.

Previously, another judge declared the law was unconstitutional because it was adopted during a special legislative session that was supposed to address improving the medical system and health of Californians.

That decision was later overturned when an appeals panel found the doctors who sued failed to show they were harmed because they could choose not to help terminally ill patients die.

Riverside County Judge Irma Asberry has told the doctors they can try to refile their case if they include patients who are opposed to the law and face undue influence to participate from family or others, said John Kappos, a partner at O’Melveny & Meyers who represents Compassion & Choices and a terminally ill man involved in the case.

He said the judge’s decision to toss out one of the doctors’ claims that the law was unconstitutional is significant.

“One challenge has been knocked out now,” he said. “There were three challenges, and now we’re down to two.”

A message was left for the plaintiffs in the suit.

In addition to California, eight states and the District of Columbia have similar measures, according to Compassion & Choices.