 Forbes played four seasons with Boston until he was claimed by the Washington Capitals in the Waiver Draft prior to the 1977–78 season.After playing one season with the Capitals, he was released after only playing two games during the 1978–79 season and signed to play for the Cincinnati Stingers of the World Hockey Association.Forbes was charged with aggravated assault in Minneapolis in 1975 after butt-ending Henry Boucha's eye socket in a game against the Minnesota North Stars, leaving Boucha with limited vision in the right eye.