A police advocacy group has criticized an appeals court judgment last week overturning a law that prevented violent felons from owning body armor, saying the ruling will put officers and the public in danger.

The decade-old ban was enacted after the 1997 North Hollywood shootout, a confrontation between police and two heavily armored bank robbers that injured officers and civilians. The state Legislature passed the ban in 1998 as a measure to protect police.

Thursday's ruling by the 2nd District Court of Appeal in Los Angeles overturned the state law, saying it was unconstitutional because the definition of body armor was too vague.

"It just makes this job that much more dangerous," said Paul Weber, president of the Los Angeles Police Protective League union for LAPD officers.

"It's going to make criminals more bold and more likely to shoot it out with the police."

The challenge to the body armor ban stemmed from the Los Angeles Police Department's 2007 arrest of Ethan Saleem, a parolee who had been convicted of voluntary manslaughter.

Saleem was arrested when police noticed that he was wearing a 10-pound, bulletproof vest underneath his shirt, according to court records.

"Certainly Saleem wasn't wearing body armor because he was going to a job interview or going on a date," the union said in a statement.

Gerald Peters, the appellate attorney who took up Saleem's case, said he didn't necessarily disagree with the spirit of the ban, just the wording.

Rather than clearly define what constituted body armor, he said, the Legislature deferred to a long, complicated set of guidelines designed for police departments.

Peters argued that only a munitions expert would be able to decipher the regulations.

"The Legislature did a botched job. They took a short cut," he said. "All they had to do was some independent thought to what they wanted to criminalize."

Weber said the notion that Saleem, or other felons, would be confused about whether or not they were wearing body armor was laughable.

"It's not like it was an extra thick T-shirt," he said. "The guy's wearing military-style body armor with a label that says body armor. I think it's pretty apparent to the guy that it was body armor."

Weber said his organization, which represents almost 10,000 officers, will ask the state attorney general's office to file an appeal, which could bring the case before the California Supreme Court.