SANTA BARBARA, Calif. — The sexual abuse of a 13-year-old scout by an adult volunteer was part of a “sordid history of child sexual abuse” within the Boy Scouts that has been documented internally by the organization for nearly a century, the victim’s attorney said Monday in his opening statement at a civil trial in California.

The scout, now 20, has sued the Boy Scouts of America and a local scouting council for punitive damages after being molested by a volunteer leader in 2007. He claims in his negligence lawsuit that the Scouts failed to educate, train and warn parents and adult volunteers about the dangers of sex abuse.

His attorney, Tim Hale, won the right to draw from more than 30 years of “perversion” files kept by the Scouts to support those allegations. The files cleared for use by Santa Barbara Superior Court Judge Donna D. Geck include 16 years of documents – from 1991 to 2007 – that have never been seen before outside the Scouts.

Hale told the jury that when the case is over they will receive a CD of 100,000 pages of files to review while they deliberate.

Hale said in his opening remarks that the Scouts recorded between 9,000 and 10,000 such files between 1920 and 2007. He intends to use documents dating from 1971 to 2007 to build his case.

“The Boy Scouts of America has a long and sordid history of child sexual abuse committed against young Scouts . committed by Scout leaders and that timeline goes back, the files show, until at least the 1920s,” he said. “What has not been going on is notice to the public and notice to (the plaintiff) and his parents.”

An attorney for the Boy Scouts countered that the “perversion” files were created to keep children safe by maintaining a master list of people ineligible to volunteer with the Scouts.

The organization acknowledges mistakes in the way sex abuse allegations were handled in the past but now has a robust child protection program and parent training, attorney Nicholas Heldt said in his opening statement to jurors.