An Oklahoma Muslim filed a federal lawsuit on Thursday to block a state constitutional amendment overwhelmingly approved by voters that would prohibit state courts from considering international law or Islamic law when deciding cases.

The measure, which got 70 percent of the vote in Tuesday's election, was one of several on Oklahoma's ballot that critics said pandered to conservatives and would move the state further to the right.

The lawsuit, filed in U.S. District Court in Oklahoma City, seeks a temporary retraining order and injunction to block the election results from being certified by the state Election Board on Nov. 9. Among other things, the lawsuit alleges the ballot measure transforms Oklahoma's Constitution into "an enduring condemnation" of Islam by singling it out for special restrictions by barring Islamic law, also known as Sharia law.

"We have a handful of politicians who have pushed an amendment onto our state ballot and then conducted a well-planned and well-funded campaign of misinformation and fear," said Muneer Awad, who filed the suit and is executive director of the Council on American-Islamic Relations in Oklahoma. "We have certain unalienable rights, and those rights cannot be taken away from me by a political campaign." About 20,000 and 30,000 Muslims live in Oklahoma, Awad estimated.

Legal experts have also questioned the measure.

Joseph Thai, a professor at the University of Oklahoma's College of Law, said the ballot measure is "an answer in search of a problem." He said he knows of no other state that has approved similar measures.

"There is no plausible danger of international law or Sharia law overtaking the legal system," Thai said in an e-mail to The Associated Press. He said courts only consider international law when deciding issues involving a federal treaty, a business contract or a will that incorporates international law.

Thai said the ballot measure "raises thorny church-state problems as well" and could even affect a state judge's ability to consider the Ten Commandments.

"The Ten Commandments, of course, is international law. It did not originate in Oklahoma or the United States," Thai said.

The measure is scheduled to go into effect on Jan. 1. It's author, Rep. Rex Duncan, R-Sand Springs, said it was not intended to attack Muslims but to prevent activist judges from relying on international law or Islamic law when ruling on legal cases.

"The threat posed by activist judges is clear," Duncan said. "It shouldn't matter what the law in France or any other European country is."

Duncan described the measure as "a pre-emptive strike" in Oklahoma, where he said activist judges are not an imminent problem. But some judges elsewhere, including U.S. Supreme Court Justice Ruth Bader Ginsburg, believe courts should look to the law of other countries for guidance when deciding cases, he said.

Ginsburg told a meeting of international lawyers in Washington in July that American judges can learn from their foreign counterparts when seeking solutions to "trying questions."

"The only people who would be a victim of this are activist judges," said Duncan, who in 2007 rejected a Quran as a gift from a council created by Gov. Brad Henry, explaining that "most Oklahomans do not endorse the idea of killing innocent women and children in the name of ideology."

One Oklahoma resident said he voted for the measure on Tuesday because chaos might ensue if judges were permitted to rely on international or religious laws in their courts.

"Any private organization could come in and say the judge has to rule according to our rules and regulations and overrule state laws," Oklahoma City attorney Jerry Fent said. "How many religions could you have?"

But Laura Gorton, a college student from Oklahoma City, said she saw no need for the measure and voted against it.

"It's not an issue here," Gorton said. "It's almost like an attempt to make a jab at other cultures."

Among the 10 other questions on Tuesday's ballot were a measure that would make English the state's official language and another one the allows residents to "opt-out" of the new federal health care reform law. Both passed.

The questions are the product of a Republican-controlled Legislature, which circumvented Oklahoma Gov. Brad Henry — a Democrat — to take them to the ballot. Critics say Republicans were trying to beef up voter turnout among certain conservative groups by appealing to biases on immigration, Islam and the reach of Washington in a state where President Barack Obama failed to win a single county in 2008.

Republicans have denied there is a conspiracy, saying that some of the measures are designed to protect citizens from the reach of the federal government.