Prince William residents may swear by their county, but until recently if they swore in it they were liable to be arrested and slapped with a $100 fine.

The county's stringent profanity law, recently struck down as unconstitutional by a Northern Virginia judge, was set aside by county supervisors yesterday as they resolved to enact a new law identical to a state statute upheld by the State Supreme Court.

The supervisors, who passed the resolution without comment yesterday, will vote on the change after a public hearing later this month.

County Attorney John Foote said that the old county law, considered the most stringent in the state, "quite simply stated that anyone who curses is guilty." He said the law was aimed at curbing "public and private usage of profanity."

Earlier this year the law was struck down as unconstitutionally vague by Prince William General District Court Judge Frank Hoss.

Under the proposed law, a person could only be arrested if he or she used "violent and abusive language calculated to breech the peace," said Foote. This law has been adopted by all other Northern Virginia jurisdictions, he said, and makes profanity a misdemeanor carrying a maximum fine of $500.

County Police Chief George Owens said people have been arrested in the county under the old profanity law for years and officers never had any difficulty deciding how to enforce it.

"We never just picked people off the streets for cursing a flat tire," he said. "It was usually something leveled at those who were being arrested and who weren't cooperating."