The ACLU argues that the law is unconstitutionally vague and overbroad and therefore cannot be used to prosecute anyone. It is vague because it does not provide notice about what language might be considered "indecent" or "insulting" or "immoral." It is overbroad because much language that might be considered insulting, indecent or immoral such as derogatory comments about Osada bin Laden is speech protected by the First Amendment.
"If the First Amendment means anything, it means that the government cannot criminalize speech just because someone finds it insulting or offensive," said Michael J. Steinberg, legal director of the ACLU of Michigan. "The Taliban might support a law giving the police the power to throw people in jail for using ‘improper' language in front of women or children. However, such a law finds no support in the U.S. Constitution. If the law remains on the books, an officer could arrest a person for making an unpopular political statement."
The case arose when Timothy Boomer, who was canoeing in the Rifle River with friends during the summer of 1999, fell out of his canoe after the canoe hit a rock in the shallow part of the river. According to testimony at trial, Mr. Boomer then swore loud enough for a family in a nearby canoe to hear.
Although the trial judge agreed with the ACLU that Mr. Boomer's words were neither obscene nor "fighting words," the judge refused to dismiss the case on constitutional grounds. Rather, the judge instructed the jury that Mr. Boomer's guilt or innocence hinged on the manner in which Mr. Boomer used the word "fuck." If the word was used as an adjective or modifier to describe the river or Mr. Boomer's frustrating day, then it was speech protected by the First Amendment. However, if Mr. Boomer repeatedly shouted the word "fuck" in a manner that did not express a thought, the judge told the jury to find him guilty. The jury found Mr. Boomer guilty. His sentence was stayed pending the outcome of this appeal.