The Indiana Court of Appeals Tuesday declared unconstitutional a 2006 state law barring registered sex offenders from living near schools, parks and youth centers in cases where the offender had already owned his home when the law took effect.

The three-judge panel’s unanimous decision, upholding a Blackford County trial court judge’s ruling from June, determined the law was “ex post facto,” meaning it effectively criminalized conduct that had not been criminal before the law took effect July 1, 2006.

Defendant Anthony W. Pollard, charged with a Class D felony sex offender registry offense, has lived in and owned his home for 20 years. In appealing the trial court ruling, the state had argued that since Pollard had violated the residency law after July 1, 2006, he was being punished merely for that violation.

“However,” the appeals court wrote, “that punishment restricts an ownership interest in property that Pollard acquired before the statute came into effect; it is not just a potential penalty for continuing to reside within the exclusionary zone after the effective date of the statute.”

St. Joseph County Police Detective Sonny Oakley, in charge of the county’s sex offender registry, said he was disappointed in the ruling but didn’t think it would have a huge impact locally. When the law took effect, there were about 30 registered offenders living within the 1000-foot exclusionary zones — about 10 percent of the county’s 320 registered offenders, Oakley said.

Oakley sent letters to the 30 offenders, 20 of whom already had moved, he said. St. Joseph Superior Court Judge John Marnocha granted relief to another six offenders who filed court petitions asking to remain in their homes, a sign that, in light of Tuesday’s ruling, Marnocha “knows the law,” Oakley said.

Marnocha could not be reached for comment late Tuesday.