Weems, a 2010 Pro Bowl special teams selection, has 2,896 kick return yards the past five seasons, seventh-best in the NFL for that time span. He had an NFL playoff record 102-yard kickoff return in the Atlanta Falcons' 2011 divisional game against the Green Bay Packers. Weems also has 41 career special teams tackles.
New Bears general manager Phil Emery was the Falcons' director of college scouting when the organization signed Weems as an undrafted rookie free agent out of Bethune-Cookman University in 2007.
The Bears made an effort to shore up special teams early in free agency. They also signed linebacker Blake Costanzo Tuesday night to help ease the potential loss of free agents Graham and fellow cornerback Zack Bowman, who recorded 10 special teams tackles for the Bears last season.
The club also had to cut special teams contributor Sam Hurd last year after he was arrested on drug-dealing charges.
While Devin Hester is the Bears' primary return man, Knox, a former special teams Pro Bowl selection himself, returned 15 kickoffs in the 2011 regular season. It's unclear when Knox will return to action after he underwent surgery to stabilize a fractured vertebra. Knox suffered the injury after absorbing a hit from Seattle Seahawks defensive end Anthony Hargrove on Dec. 18.
Weems' arrival gives the Bears insurance in case Knox's road to recovery is a long one.