He played college football at Maryland and was selected by the Pittsburgh Steelers in the second round of the 2016 NFL draft.
He has also been a member of the Washington Football Team, Indianapolis Colts, Cincinnati Bengals, New England Patriots, and Houston Roughnecks.
He received offers from North Carolina, Boston College, and Connecticut but ultimately chose to attend the University of Maryland to play football.
Multiple teams and scouts had Davis listed as a safety instead of cornerback because of his size, athleticism, and tendency to give up big plays in coverage.
It was reported up to 19 NFL teams were interested in him and he had visits with New England Patriots head coach Bill Belichick and the Tampa Bay Buccaneers.
[11] Davis began training camp developing as the Steelers' future strong safety and competed against Robert Golden for the starting role, but was forced to play the nickel position after Senquez Golson suffered a foot injury.
[14] During a Week 3 loss to the Philadelphia Eagles, he finished with a total of seven combined tackles and also suffered an injury to his back during the game.
[14] On October 9, 2016, he was again the Steelers' starting nickel back against the New York Jets and would finish the game with four solo tackles and six total.
[13] On November 13, 2016, Davis made a critical penalty when he grabbed the face mask of Cowboys tight end Jason Witten with less than 30 seconds left in the fourth quarter.
[15] The following week, Davis replaced Robert Golden as the Steelers' starting strong safety in a victory over the Cleveland Browns and finished the game with three combined tackles and a pass deflection.
Late in the second quarter, Davis saved a go-ahead touchdown after stopping quarterback Scott Tolzien at the one-yard line after he attempted to dive into the end zone.
[20] During the offseason, Davis had surgery to repair a torn labrum he suffered while making a tackle in a Week 3 loss against the Philadelphia Eagles.
[21] Head coach Mike Tomlin stated Davis would remain the starting strong safety to begin the regular season.
On December 31, 2017, Davis collected three combined tackles, deflected a pass, and made a sack and interception on quarterback DeShone Kizer in the Steelers' 28–24 victory.
[40] Davis was elevated to the active roster on December 6 for the team's week 13 against the Buffalo Bills, and reverted to the practice squad after the game.
[43] The Roughnecks brand was transferred to the Houston Gamblers when the XFL and USFL merged to create the United Football League (UFL).
[2] On February 26, 2018, it was reported that Davis was named as a defendant in a civil lawsuit for allegedly posting a Snapchat video that led to the bullying of a teen at school.