The 5-foot-9, 184-pound Mouton could compete for playing time inside. He notched 44 tackles in 13 games (two starts) for Tennessee in 2012.
Mouton, 26, was a third-round pick of the Titans in 2009. He’s appeared in 36 career regular-season games, recording 61 tackles and defending three passes.
A first-year pro, Gumbs (5-10, 210) had a stint on the Chiefs’ practice squad last season. The 25-year-old safety signed as an undrafted free agent with New Orleans in 2012.
Washington also announced starting cornerback Josh Wilson was removed from the active / physically unable to perform list after passing a physical.