DES MOINES, Iowa — Two state laws that prohibit misuse and desecration of an American flag are unenforceable and unconstitutional, a federal judge has ruled.

U.S. District Judge Robert W. Pratt said yesterday that the Iowa laws violate the 14th Amendment's due-process clause. However, Pratt rejected assertions that the laws violated the First Amendment protection of free speech.

The American Civil Liberties Union of Iowa brought a lawsuit on behalf of a man charged with a misdemeanor for flying a flag upside down and writing on it and another man also charged with flying a flag upside down. It declared the ruling a victory.

"Today should mark the end of government misuse of these laws to intimidate and harass those who disagree with government policies," said Ben Stone, ACLU of Iowa executive director, in a statement.

Kathy Nees, state program director for the American Legion of Iowa, said the ruling in Roe v. Milligan would upset many veterans and others who have fought for a federal constitutional amendment to ban flag desecration.

"I think it's definitely going the wrong direction and sending the wrong message," she said.

Scott Wayne Roe of Ottumwa displayed a U.S. flag upside down on June 4, 2006, and wrote "Corruption of Blood" across it, saying he was protesting city ordinances and how they were enforced. He was charged with a misdemeanor, but the charge was dismissed.

Dale Klyn of Corydon displayed his flag upside down to protest what he called an unfair loss in a bankruptcy case and to support a campaign for mental-health care services for veterans. His case was also dismissed.

Pratt struck down a portion of the state's disorderly conduct code, which makes it a simple misdemeanor to "knowingly and publicly use the flag as to show disrespect for the flag as a symbol of the United States," and a state code that prohibits desecration of the flag.