Washington and a friend were driving from one city in Oklahoma to another. The car was a rental borrowed from Washington's passenger's mother, and there was a shit ton of weed in it. They got caught, and convicted of distribution, and appealed.
Washington's friend's conviction stood, but this is Washington's case. The Tenth Circuit held that his mere presence in the car, even combined with speculation about what he might have known, was not enough to find beyond reasonable doubt that he knew about the drugs in the car (particularly given that he was not the only one in the car). Apparently, there was stronger evidence tying his friend to the drugs.