8:38 AM PT -- TMZ Sports has obtained the police report ... which says Woods is being accused of "tampering with evidence" because he allegedly put a lit joint in a water bottle.
Here's the deal ... cops say Woods was pulled over around 11:15 PM for going 77 in a 60.
During the stop, the officer smelled weed and believed Woods was stoned -- and asked if there was weed inside the vehicle.
Woods allegedly admitted to having a bunch of marijuana in the car. The officer says Woods had a backpack containing 2 mason jars of weed and a small gold cylinder of weed.