Updated

The first criminal case involving "sexting" reached a U.S. appeals court on Friday — a case that asks whether racy cell-phone photos of three girls amount to child pornography or child's play.

A county prosecutor in northeastern Pennsylvania threatened to pursue felony charges if the girls skipped his "re-education" course on such topics as sexual predators and "what it means to be a girl in today's society."

The photos show two 12-year-olds in training bras at a sleepover and a topless 16-year-old stepping out of the shower.

MaryJo Miller, 45, of Tunkhannock, Pennsylvania, thought her daughter Marissa and friend Grace Kelly were being "goofballs" in the 2007 slumber-party shot, which mysteriously surfaced two years later in student cell phones confiscated at school.

"You're going to see more provocative photos in a Victoria's Secret catalog," Miller, a classroom aide in the Tunkhannock Area School District, said after the hearing, referring to the lingerie retailer.

County officials say they are trying to address the pervasive problem of teens sexting, or exchanging sexually explicit photos and e-mails on their cell phones. According to one study, 20 percent of U.S. teens admit they have done it.

The American Civil Liberties Union considers the images in the Pennsylvania case harmless.

"We've been mystified how anybody can look at these photos and say these are second-degree felonies," Witold J. Walczak, the ACLU of Pennsylvania's legal director, argued Friday in the U.S. 3rd Circuit Court of Appeals.

Either way, he said, officials are flipping the intent of child-pornography laws — to protect children — by going after the victims. It's unclear who first disseminated the photographs. Each girl insists she did not.

"Turning them into sex offenders is an odd way to protect kids," Walczak said after the oral arguments.

Former Wyoming County District Attorney George Skumanick Jr., a Republican, initiated the case in late 2008, and successor Jeffrey Mitchell, a Democrat who took office this month, shows no sign he'll change course.

"Naked pictures of children on the Internet draws predators the same way a swamp draws mosquitoes," argued lawyer Michael Donohue of Scranton, who represents the prosecutor's office. Authorities must sometimes protect children from themselves, he argued.

The judges appeared dubious of the "re-education" class, honing in on the ACLU argument that it amounts to compelled speech. Judge Thomas Ambro asked whether government should require a course on what it means to be a girl in society, as taught by a county official.

Walczak believes officials are infringing on parents' right to control and educate their children. The 13 other Tunkhannock students accused of sexting — three boys and 10 girls — chose to attend the $100, six- to nine-month pretrial diversion program.

"Sexting is a vague term that covers everything from the lovely to the laughable to the lewd," Walczak said. "Just because his sensibilities are offended, he cannot impose his particular orthodoxy."

Donohue argued that minors exchange provocative images for the "sexual stimulation and gratification" of fellow students.

Still, he said the county no longer plans to pursue charges over the bra photo, but only over the topless shot, which involves a girl identified as "Nancy Doe."

School officials in Tunkhannock, about 130 miles north of Philadelphia, found the images in late 2008 on cell phones confiscated from junior and senior high school students. They ranged in age from 11 to 17.

Prosecutors in a number of states, including Pennsylvania, Connecticut, North Dakota, Ohio, Utah, Vermont, Virginia and Wisconsin, have tried to put a stop to sexting by charging teens who send and receive the pictures.

The 3rd Circuit judges did not indicate when they would rule.

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