The American Civil Liberties Union sued the city of Plattsmouth on Thursday for refusing to take down a Ten Commandments monument that has been displayed in a city park since 1965.

The lawsuit, filed in U.S. District Court in Lincoln, alleges that the display violates the First Amendment and subsequent U.S. Supreme Court rulings on a separation of church and state.

Nebraska ACLU Executive Director Tim Butz said negotiations with the city failed, prompting the lawsuit.

"The city of Plattsmouth has no business telling its citizens that a certain set of religious tenets are preferred by the city government," he said. "In America, individuals have the autonomy to develop their own set of beliefs and are free to embrace or reject religion without dictates from the government."

City Attorney Roger Johnson said he had not seen the lawsuit and could not comment, but the case would be handled by the American Center of Law and Justice, a conservative, Virginia-based group that has fought the ACLU on several similar cases.

Frank Manion, an attorney for the center, said he was confident the city could win the case.

"There is absolutely no constitutional violation involved in a city's display of a monument of this sort, which displays a text which has played a vital and fundamental role in the development of western legal systems," he said. "That fact has been recognized by the U.S. Supreme Court on many occasions."

More than 4,000 similar monuments are displayed in cities around the United States.

The center has asked the high court to review a lower court order that said a Ten Commandments display in Elkhart, Ind., had to be taken down.

Alabama, Mississippi, Nebraska, North Dakota, Ohio, South Carolina and Texas have filed friend of the court briefs in the Supreme Court case.

The brief argues the Ten Commandments should not be viewed strictly as a religious document but one that also has historical, cultural, moral and literary qualities.

The high court has until June to decide if it will hear Elkhart's case.

About 60 Plattsmouth residents voiced their support for keeping the monument at a City Council meeting last year.

Butz has said the marker has no historical significance and should not be on public property.

Similar monuments in Fremont, Hastings and Falls City also are under scrutiny by the ACLU.

"But we want to see how this lawsuit goes first," Butz said.

Last year, Wilkes County, N.C., and the ACLU reached a settlement over the display of the Ten Commandments in the county courthouse. The county agreed to replace Ten Commandment plaques with displays about the Constitution.

Earlier this year in Grand Junction, Colo., officials responded to an ACLU complaint about a Ten Commandment monument outside of city hall by adding a sign disavowing intent to establish a religion.

Also this year, a federal judge refused to jail officials of three Kentucky counties for posting the Ten Commandments in public buildings, and ordered the ACLU and the counties to try to settle the dispute.

The judge ordered the displays taken down after the ACLU filed a lawsuit challenging their constitutionality. Each of the counties obeyed her order, but then replaced the former displays with new ones that included the commandments along with documents such as the Declaration of Independence and the Bill of Rights.

Last year, a federal judge ordered officials in Lawrence County, Ind., to remove a monument inscribed with the Ten Commandments from the courthouse lawn.