ATLANTA — A man who sent obscene material to minors over the Internet is not required to register as a sex offender because his particular crime was not on the list in the federal statute mandating registration, a three-judge federal panel ruled Wednesday.

In a 2-1 decision, the 11th U.S. Circuit Court of Appeals panel overturned an order by U.S. District Judge Callie V.S. Granade of Mobile, Ala.

Granade sentenced Matthew Mason Dodge on Jan. 17, 2008 to 18 months in prison, three years of probation and required him to register as a “tier 1,” offender, the lowest level, requiring registration for 15 years.

Dodge pleaded guilty to transferring obscene material to a minor. He admitted providing links to nude photos of himself to a person he thought was a teenage girl but who was actually a police officer.

“Although Dodge transmitted obscene material to persons he believed to be minors, he did not engage in conduct that constitutes a ‘sex offense against a minor’ as we understand that phrase,” said the opinion by Circuit Judge Rosemary Barkett and Judge Donald C. Pogue of the U.S. Court of International Trade, sitting by designation.

The judges noted the subsection of the federal Sex Offender Registration and Notification Act listing the various offenses requiring registration. Dodge’s was not among them, nor could it be stretched to fit the others, they said.

“Dodge’s actions, offensive and deplorable though they may be, lack any element of an unwanted sexual assault, offense or other violation that contacts or opposes a minor’s rights,” the opinion said.

Circuit Judge Charles R. Wilson dissented, saying Dodge clearly engaged in conduct that “by its nature is a sex offense against a minor.”

Prosecutors in the U.S. Attorney’s Office in Mobile did not return telephone calls seeking comment.

Dodge’s lawyer, Kristen Gartman Rogers of the Federal Public Defender’s Office, said because of Wilson’s dissent and the intricacies of the ruling she expects the government to appeal.

“This opinion is very narrow,” Rogers said.

She said it would not apply to other sex offenders, such as those caught arranging trysts with minors, or those they believe to be minors, over the Internet.