ESPN's Adam Schefter added that the Trufant signing will enable the Lions to continue looking for a trade partner for cornerback Darius Slay.
Trufant, who made the Pro Bowl after a stellar 2015 season, started seven years for the Falcons after they took him 22nd overall in the 2013 NFL draft.
The 29-year-old has racked up 13 interceptions, 79 passes defended and 329 tackles throughout his career. He hauled in a career-high four picks in only nine games last year.
However, Trufant also struggled in coverage, allowing 11.6 yards per target and 17.6 yards per completion in 2019, per Pro Football Reference.
Still, he was mostly key for the Falcons throughout the past seven years, which included a pair of postseason appearances and a near-win in Super Bowl LI over the New England Patriots. He could be a great asset for the Lions as they retool their defensive backfield.
The Lions finished 29th in pass-defense DVOA (defense-adjusted value over average) last season, per Football Outsiders. They were also tied for 29th in net passing yards allowed per attempt at 7.1, per Pro Football Reference.
Detroit is undergoing an overhaul of its defense, signing linebacker Jamie Collins and defensive tackles Nick Williams and Danny Shelton. The Lions also traded for New England Patriots safety Duron Harmon and released linebacker Devon Kennard and defensive tackle Damon Harrison.
Trufant will thus be tasked with helping the Lions defense excel despite the many changing faces heading into Matt Patricia's third year as head coach.