Rob Reiner is developing a film based on the legal challenge to Proposition 8, California's gay marriage ban.

Proposition 8's 2008 approval put an end to the marriages of gay and lesbian couples taking place in the state after a California Supreme Court ruling legalized gay marriage.

Reiner told The Hollywood Reporter that his upcoming film “is based a little bit on the court challenge to Proposition 8, which I have been involved in.”

Reiner is a co-founder of the American Foundation for Equal Rights (AFER), the group formed specifically to challenge the constitutionality of the amendment.

“We have been involved every step of the way,” he added. “Right now, we're waiting for the Ninth Circuit to come with their appeal decision. Either we'll win, and it will be expunged in California. If it gets appealed, it might go to the U.S. Supreme Court.”

AFER has already backed a play based on last year's 13-day trial, which found Proposition 8 to be unconstitutional. 8, which was written by Dustin Lance Black (Milk), raised $1 million for AFER during last month's one-night celebrity reading in New York.