His post-playing years were troubled. In 2014, Barber was detained by the police in Mansfield, Texas, also outside Dallas, and hospitalized for a mental health evaluation.
And according to police reports, he was arrested in 2019 on two misdemeanor counts of criminal mischief for incidents that occurred the year before in which, while he was out jogging, Barber approached two different cars and struck and damaged them. He pleaded no contest, and his sentence included 12 months of probation.
Last year, the former Dallas wide receiver Dez Bryant posted a highlight reel of Barber’s plays on Twitter and wrote that “he’s down and out bad … we are just a stat and moments to most people.”
On Monday, Bryant wrote on Twitter: “Too much to digest, so much too say … This is real life, it can be any of us. We need each other, we need unity.”
Marion Sylvester Barber III was born on June 10, 1983, in Plymouth, Minn., west of Minneapolis. Like his father, Barber played at the University of Minnesota, where he was part of a powerful backfield with Laurence Maroney. Barber rushed for 1,196 yards and 1,269 yards in 2003 and 2004.
The Cowboys selected him in the fourth round of the 2005 N.F.L. draft.
Football was a family business for the Barbers. In addition to his father, Barber’s brothers Thomas and Dominique also played for the University of Minnesota Gophers. Dominque was a defensive back with the N.F.L.’s Houston Texans.
In a statement on Thursday, P.J. Fleck, the Gophers’ head coach, said, “Marion was one of the best to ever play at Minnesota, and he is a big reason many people are Gopher fans today.”