PHILADELPHIA -- A federal appeals court Wednesday decided not to decide whether photos in a "sexting" controversy are free speech protected by the First Amendment.

But the three judges in Philadelphia said a prosecutor could not charge a teenage girl merely for appearing in a photograph without evidence she had engaged in distributing it.

The case before the U.S. Court of Appeals for the 3rd Circuit gained national attention this year because it was, potentially, the first appeals case to address whether free-speech law protected "sexting" -- sending sexually explicit messages or photos to cell phones.

The controversy started in October 2008, when officials in the Tunkhannock School District, north of Scranton, found photos of nude and semi-nude girls on male students' phones.

The Wyoming County district attorney at the time, George Skumanick Jr., told parents that any student who appeared in a photo and did not attend an "education program" of his choosing would face child pornography charges.

Three parents sued rather than send their children to the course, and they obtained an injunction from U.S. District Court prohibiting criminal charges. Mr. Skumanick appealed.

The court said in January that it wanted to consider the First Amendment issue, but on Wednesday the judges stated in their 35-page decision that "we decline to consider it."

The court did rule that the district attorney had been wrong to threaten to charge the teen merely for refusing to attend the program.

The case involved photos of two 12-year-old girls in training bras and the 16-year-old wrapped in a towel, with her breasts exposed, as she leaves a shower.

Mr. Skumanick's attorney, Michael J. Donohue of Scranton, said he was "disappointed" by the decision, but added that he was pleased "the court did not hold that the transmission of photographs of naked children by other children is protected by the First Amendment."

Witold J. Walczak, an American Civil Liberties Union attorney who represented the girls and their mothers, said, "The decision sends a message to prosecutors that there are constitutional limits to their authority to charge kids involved in sexting."

"The DA could not charge these girls simply for appearing in the photos," he said.

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