In some cases, scoutmasters were flagged in Boy Scouts files only after they were convicted of sexual abuse and news of their wrongdoing was reported.

Deron Smith, national spokesman for the Boy Scouts of America, said the organization keeps a list of ineligible volunteers and works closely with law enforcement when abuse is reported.

“There are cases in there that we believe were handled inappropriately, but you’re looking at a different era,” he said. “Today we take a multi­tiered approach to keeping kids safe.”

Smith said the Scouts now require national criminal background checks from all prospective adult leaders, and a Scout leader is never allowed to be alone with a boy.

Mark Nelson of Kingston, the Scout executive of the Annawon Council, learned of the files when he began working for the Scouts as a district executive in 1985 while in Arizona.

“It’s one tool in an arsenal to protect our youth,” he said. “Its main purpose has been to keep track of individuals that could not meet our standards of membership, or we’d be concerned with them being ­involved with youth.”

Matthew Fogelman, an ­attorney who represents victims of childhood sexual abuse, said Friday that the Boy Scouts erred by failing to make public the files on alleged abusers.

Fogelman said the publication of those incidents would have hastened changes to Boy Scout regulations, including the rule that adult leaders may not sleep alone in a tent with a boy, that may have prevented later abuse.

“I’m not saying that the Boy Scouts should be abolished,” Fogelman said. “But if the idea is to prevent other people from being injured or abused, you need more information than less information for that to happen.”

Though much time has passed since the incidents covered in the perversion files occurred, Capeless said his office could possibly prosecute ­offenders through exceptions to the statute of limitations, but only if a victim came forward.

“I would be loath to resurrect a situation like this unless a victim wanted that,” Capeless said in an interview Friday.

“I don’t think it’s my place to bring this up again, only to find out that someone didn’t want that and to retraumatize them,” he said.

In separate statements, ­Attorney General Martha ­Coakley, Middlesex District ­Attorney Gerard T. Leone Jr., and Suffolk District Attorney Daniel F. Conley all condemned the Boy Scouts’ use of a secret database of abusers.