An amendment that would ban Oklahoma courts from considering international or Islamic law discriminates against religions and a Muslim community leader has the right to challenge its constitutionality, a federal appeals court said Tuesday.

The court in Denver upheld U.S. District Judge Vicki Miles-LaGrange's order blocking implementation of the amendment shortly after it was approved by 70 percent of Oklahoma voters in November 2010.

Muneer Awad, the executive director of the Council on American-Islamic Relations in Oklahoma, sued to block the law from taking effect, arguing that the Save Our State Amendment violated his First Amendment rights.

The amendment read, in part: "The courts shall not look to the legal precepts of other nations or cultures. Specifically, the courts shall not consider international law or Sharia law."

Backers argued that the amendment intended to ban all religious laws, that Islamic law was merely named as an example and that it wasn't meant as a specific attack on Muslims. The court disagreed.

"That argument conflicts with the amendment's plain language, which mentions Sharia law in two places," the appeals court opinion said.

The court also noted that the backers of the amendment admitted they did not know of any instance when an Oklahoma court applied Sharia law or used the legal precepts of other countries.

Awad argued that the ban on Islamic law would likely affect every aspect of his life as well as the execution of his will after his death. The appeals court pointed out that Awad made a "strong showing" of potential harm.

"When the law that voters wish to enact is likely unconstitutional, their interests do not outweigh Mr. Awad's in having his constitutional rights protected," the court said.