The upcoming film is based on the true story about three teenagers accused and convicted of killing three young children in 1993.
Linn will play the real-life Chief Inspector Gary Gitchell, who led the investigation and then left the Memphis police department after the three teens were convicted, reports Deadline.
Devil's Knot already stars Reese Witherspoon, Colin Firth, Mireille Enos and Amy Ryan.
Linn was previously seen in CSI: Miami, which was axed after ten seasons by CBS.
Next up for the actor is the Quentin Tarantino-directed movie Django Unchained, starring Jamie Foxx, Leonardo DiCaprio, Christophe Waltz and Kerry Washington.
Watch the trailer for Django Unchained below: