Criminals and bad-deed doers might soon be learning something NFL offensive players long knew: Do not — repeat, do not — mess with Charles Tillman.

Tillman, the former cornerback for the Chicago Bears and Carolina Panthers, is training to become an FBI agent, according to the Chicago Tribune and ESPN. The player nicknamed “Peanut” by a relative for how he looked as a baby happens to have earned a degree in criminal justice at Louisiana-Lafayette and presently is at the FBI Training Academy in Quantico, Va.

Tillman spent the bulk of his career with the Bears, who took him with the 35th overall pick in the second round of the 2003 NFL Draft. During his 13 seasons in the league, he often observed and worked with law enforcement officials, the Tribune’s Brad Biggs reports, and at 36, he falls just within the FBI’s 23-to-37 age parameters. Tillman’s last NFL season was in 2015, when he and the Panthers advanced to the Super Bowl. He spent one season in Carolina and signed a one-day contract with the Bears to retire as a member of the team in 2016.

Tillman, whose father was an Army sergeant, was active in military affairs as a player, visiting Iraq and Kuwait on a USO Tour in 2010 and was given the NFL’s Salute to Service award in 2012. His foundation also has been actively working with children’s charities, particularly since his baby daughter underwent a heart transplant in 2008.

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