Washington, 26, is a former third-round pick of the Bills back in 2016. He was in the third year of his four-year, $3.189 million contract when the Bills waived him prior to the 2018 season.
The Cowboys signed him to their practice squad before the Bengals added him to their preseason roster in September, but was waived soon after. He caught on with the Dolphins but was among their final roster cuts.
Since becoming a free agent, Washington has worked out for the Redskins, Packers, and Chargers but left each meeting without a contract.
In 2018, Washington appeared in five games and recorded eight tackles and a sack.