Jenkins, 26, was second-round pick out of Clemson by the Redskins in 2011, but missed his entire rookie season after tearing his ACL in training camp.
He started 33 games for Washington during the last three seasons. In 2014, he had 28 combined tackles and zero sacks.
Jenkins joins a defense that finished No. 30 in yards allowed and No. 31 in scoring defense last season. Defensive coordinator Mel Tucker was fired and replaced by Vic Fangio, and head coach Marc Trestman was also fired and replaced by John Fox.
- Paul Palladino