SAN DIEGO — A San Diego lawyer was at the center of the fight to prove a young man’s innocence after he was falsely accused of rape — a story adapted for a new movie screening Saturday in Balboa Park.

The film is based on the story of Brian Banks, a man who was successfully exonerated by the California Innocence Project and then went on to play in the NFL.

Banks was a standout linebacker at Long Beach Poly in the Los Angeles area when he was accused of sexually assaulting a classmate on campus in the summer of 2002. Facing a possible 41-year to life sentence, Banks took a plea deal for five years of prison and another five years of probation, plus registering as a sex offender.

Banks spent nearly six years behind bars and another four years on parole. Eventually he attracted the attention of the California Innocence Project, which helped him fight for his exoneration. While his accuser at one point admitted on video that she had made up the story, it took additional evidence and further legal maneuvering to finally get a judge to dismiss all charges against Banks in May 2012 and release him from sex-offender status.

Banks went on to play professional football for the now-defunct United Football League, and briefly signed with the NFL’s Atlanta Falcons.

Justin Brooks, a criminal defense attorney and the director of CIP, is a tenured professor at San Diego’s California Western School of Law. Justin is portrayed in the new film, “Brian Banks,” by Greg Kinnear and is an executive producer of the film.