Bruce Jenner has volunteered all of his cell phone info to the L.A. County Sheriff's Dept. to prove he was not texting at the time of Saturday's fatal car crash.
Law enforcement sources tell TMZ ... Jenner has authorized Sheriff's detectives to get all the necessary data from Jenner's cell phone carrier, thus making a search warrant unnecessary.
We're told Jenner's promise was verbal but the Dept. needs it in writing in order to gain access to the info.
As we reported, an independent photo agency was at the scene immediately before the crash and snapped a pic of Jenner holding a cigarette and not a cell phone.
We're told it's highly improbable Bruce will be charged with a crime, but civilly he has a problem because there's a law about following too close. Even though it now appears the Prius in front made a sudden stop causing the Lexus to crash into it and Bruce then hit the Lexus ... law enforcement says Bruce should have been farther behind the Lexus, especially since he was pulling a trailer.