Owen Wilson chose morality over money when the director of an O.J. Simpson movie dangled a pretty massive check in front of his face.

Joshua Newton says he offered Owen $12 MILLION to play Douglas McCann, a real-life attorney who got wrapped up in various conspiracy theories during O.J.’s 1995 murder trial.

Newton says Owen backed out after he read the whole script and realized that it suggested O.J. was INNOCENT.

Owen supposedly told him, quote, “If you think I’m going to take the lead role in a movie about how O.J. didn’t do it, you’ve got to be kidding me!”

The movie’s actually been in development for NINE YEARS . . . and not much of it has been shot yet.  But Newton did release a brief teaser featuring O.J., played by actor Boris Kodjoe . . . in the ELECTRIC CHAIR.

(TMZ)