Dunbar attended Corcoran High School in Syracuse, New York[1] where he played running back and linebacker, under the head coach Leo Cosgrove.

[2] During his senior year at Boston College, Dunbar received recognition by becoming the fourth player in NCAA history to return two fumbles for touchdowns in a single game.

[4] In Week 1 of the 2012 season against the Detroit Lions, Dunbar recorded his first career interception, returning it 42 yards.

He finished his first season with the Rams with 114 combined tackles, 4.5 sacks and two interceptions which were all career highs for him at the time.

[7] After he was released by St. Louis, the Saints signed Dunbar on October 30, 2015 to provide depth in light of injuries to starting linebackers Dannell Ellerbe and David Hawthorne.