Mazurek v. Armstrong, 520 U.S. 968 (1997), was a United States Supreme Court case in which the Court upheld a Montana law permitting only licensed physicians to perform abortions. The Court summarily reversed a ruling of the United States Court of Appeals for the Ninth Circuit that had held that the law was likely intended to inhibit abortion access. In a per curiam opinion, a majority of the Court found that there was no evidence that the Montana legislature acted with an invalid intent. The Court also reiterated its earlier holding in Planned Parenthood v. Casey that the states have broad flexibility to regulate abortion so long as their regulations do not create an undue burden on a woman's right to choose. Three dissenting justices, in an opinion by Justice John Paul Stevens, wrote tha