(CNN) -- A federal judge has extended a temporary restraining order against an Oklahoma referendum that would ban the use of Islamic religious law in state courts.
Oklahoma voters approved the amendment during the November elections by a 7-3 ratio. But the Council on American-Islamic Relations challenged the measure as a violation of the First Amendment to the U.S. Constitution.
U.S. District Judge Vicki Miles-LaGrange issued a temporary restraining order November 8 that will keep state election officials from certifying that vote.
On Monday, she ruled that the temporary restraining order will remain in place while she makes a final decision on whether to issue a permanent injunction until the case is resolved. That final decision will come no later than November 29, she said.
"What this amendment is going to do is officially disfavor and condemn the Muslim community as being a threat to Oklahoma," Muneer Awad, executive director of CAIR's Oklahoma chapter and the lead plaintiff in the suit, said earlier this month. In addition, he said, the amendment would invalidate private documents, such as wills, that are written in compliance with Muslim law.
The amendment would require Oklahoma courts to "rely on federal and state law when deciding cases" and "forbids courts from considering or using" either international law or Islamic religious law, known as Sharia, which the amendment defined as being based on the Quran and the teachings of the Prophet Mohammed.
In bringing suit, CAIR argued that the amendment violates both the establishment and free-exercise clauses of the First Amendment's guarantee of religious freedom. Awad has said the amendment passed "under a campaign of fearmongering" about Islam.
The entire U.S. Muslim population is about 2.4 million -- less than 1 percent of the country, according to a 2009 survey by the nonprofit Pew Forum on Religion and Public Life.
But supporters said a New Jersey case, in which a judge refused to grant a restraining order against a Muslim man whose wife accused him of raping her repeatedly, made it necessary for Oklahoma to take action to keep Islamic law from being imposed there.
The New Jersey decision, in which the family court judge found the husband was abiding by his Muslim beliefs regarding spousal duties, was overruled by an appellate court.
But in automated phone messages in support of the amendment, former CIA Director and Oklahoma native James Woolsey warned that there was a "major campaign in Europe to impose Sharia law" and that Islamic law "is beginning to be cited in a few U.S courts."
CNN's Matt Smith contributed to this report