By Andrew Chung

WASHINGTON (Reuters) – The U.S. Supreme Court on Tuesday struck down a California law requiring clinics that counsel women against abortion to notify clients of the availability of abortions paid for by the state, ruling it violated the free speech rights of these Christian-based facilities.

The Supreme Court legalized abortion in 1973, and while the broader issue of abortion rights was not at issue in the case, the 5-4 ruling represented a significant victory for abortion opponents who operate these kinds of clinics – called crisis pregnancy centers – around the country.

The court’s five conservative justices were in the majority in the ruling authored by Justice Clarence Thomas, with the four liberals dissenting.

Crisis pregnancy centers have said they offer legitimate health services but that it is their mission to steer women with unplanned pregnancies away from abortion.

There are roughly 2,700 crisis pregnancy centers in the United States, including around 200 in California, according to abortion rights advocates, vastly outnumbering abortion clinics. California officials said some of the centers mislead women by presenting themselves as full-service reproductive healthcare facilities, going so far as to resemble medical clinics, down to lab coats worn by staff.

California’s Reproductive FACT Act, passed by a Democratic-led legislature and signed by Democratic Governor Jerry Brown in 2015, required centers licensed by the state as family planning facilities to post or distribute notices that the state has programs offering free or low-cost birth control, prenatal care and abortion services. The law also mandated unlicensed centers that may have no medical provider on staff to disclose that fact.

(Reporting by Andrew Chung; Editing by Will Dunham)