The actor - who also appears on Covert Affairs - joins Mira Sorvino in the crime series from producer Jerry Bruckheimer.
Bailey will play the partner of Sorvino's state trooper - a widowed father and "by-the-book" officer, according to Deadline.
The 36-year-old's past credits include HBO's Band of Brothers and the films Fight Club and Almost Famous.
Trooper was originally developed at CBS last pilot season, but the project was ultimately revived by TNT in September.
In the original CBS pilot, Bailey's role was played by actor Jay Hernandez (Last Resort, Hostel).
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