A former district court bailiff who offered a couple $50 an hour to videotape them having sex is not guilty of prostitution, because there was no evidence he was satisfying his own sexual pleasure, the state Supreme Court ruled yesterday.

To find otherwise, the court ruled, would illegally criminalize the production of a sexually explicit but not obscene movie, a venture that is protected as free speech under the state constitution.

The ruling is a win for Robert Theriault, 51, of West Ossipee, a former bailiff at Franklin District Court. But only partially. Theriault remains convicted of a second charge of prostitution involving another couple. The cases are similar, but the Supreme Court saw an important distinction between them.

In the first case, Theriault was convicted of offering a couple money to watch them have sexual intercourse. In New Hampshire, it is against the law to pay, agree to pay or offer to pay someone to have sex or sexual contact. No one needs to actually engage in sex for a charge to be brought.

A jury convicted Theriault in that case, and he appealed. His attorney argued that, in theory, the state's prostitution law is too broad because it could be applied to activities that are, in fact, protected, such as the making of movies. The entire law, his attorney said, should be thrown out.

The state Supreme Court rejected that argument in May, saying that Theriault and his attorney had not alleged a specific problem with the law but had rather argued a general, theoretical failing. There may be instances where the law could be illegally applied, such as the making of a sexually explicit movie, but Theriault hadn't made a specific enough argument, the court ruled.

Theriault's attorney was more specific in the second case, and that appears to have made a difference.

In that case, Theriault was again convicted of prostitution, this time for offering to pay a couple to videotape them having sexual intercourse. On that appeal, Theriault's attorney focused on Theriault's intent - not the fairness of the overall law.

The defense said Theriault needed to act for his own sexual gratification when he approached the couple to be guilty of prostitution. And there was no evidence at trial, the defense said, that he was motivated by his own gratification.

Instead, the defense said, Theriault was simply making the kind of sexually explicit movie that is protected speech under the state constitution. The justices agreed.

"There was no evidence or allegation that the defendant solicited this activity for the purpose of sexual arousal or gratification as opposed to making a video," the court ruled.

The court continued: "There was, therefore, no finding by the trial court that (Theriault's) request to make a movie was for an illegitimate purpose."

But the court did not rule out the possibility that the state could never outlaw the making of pornography. But to do so, the state must show the filmmaker was in it for his own sexual arousal, the court said.

Merrimack County prosecutor Wayne Coull, who prosecuted Theriault in both cases, said yesterday he had not decided how to respond to the ruling. If the statute of limitations has not expired, Coull could charge Theriault again.

But a second conviction is not likely to significantly change Theriault's sentence. He received 150 hours of community service for the conviction that was upheld by the high court. The conviction overturned yesterday added 50 hours of community service to Theriault's obligation.