Cooper DeJean's brother is in trouble with the law ... cause TMZ has learned Beckett DeJean was arrested for operating while intoxicated.
According to jail records, seen by TMZ, Beckett was taken into custody Sunday morning in Idaho on a first offense DUI/OWI, which is classified as a misdemeanor but still carries serious penalties.
Beckett was a defensive back for the South Dakota Coyotes, where he played as a redshirt freshman. Beckett's older brother Cooper is currently an NFL cornerback for the Philadelphia Eagles.