(Portland, OR)  --  A man is facing charges of criminal mischief, after being accused of spitting on a TriMet driver and using a racial epithet against him.  David Wade Morgan is also charged with intimidation in connection with the April 23rd incident aboard a TriMet bus in Portland.  Police say the driver told them Morgan had spit on him a couple of weeks before the incident, and banned Morgan from riding the bus as a result.  Authorities say Morgan is accused of spitting in the driver's face three times and breaking off the passenger-side windshield wiper after the driver closed the door.