(Portland, OR)  --  A former Portland Police officer is facing several charges after allegedly running down a man with his car at a protest in June.  The Marion County District Attorney's Office says Scott Groshong was arraigned on several charges Monday including third-degree assault and hit-and-run.  Groshong is accused of using an unmarked police car while working undercover to run down a suspect accused of stealing.  He retired in August after 27 years as a police officer.