He was signed by the St. Louis Rams as an undrafted free agent on April 26, 2010, but was released one month later.
Hartford Colonials/Philadelphia Eagles
Lawrence was then drafted by the Hartford Colonials 22nd overall in the 2010 UFL Draft on June 2, 2010, but signed with the Philadelphia Eagles on June 8. He was part of the Eagles' final cuts on August 28 and joined the Colonials instead, playing in eight games for the team.
After the conclusion of the 2010 UFL season, he signed with the Chicago Bears on December 14, 2010 and spent three weeks on the team's practice roster.
He then joined the Tampa Bay Buccaneers on December 30, 2010 and participated in the team's training camp for the 2011 season. However, he was released on September 3, 2011.
Lawrence signed with the Edmonton Eskimos of the Canadian Football League on January 10, 2012, playing in 15 games and starting one. Over the course of the season Lawrence contributed 15 tackles, 11 special teams tackles and 1 fumble recovery.
Hamilton Tiger-Cats
During the following off-season, he was traded to the Hamilton Tiger-Cats with Greg Wojt and Jeremiah Masoli for Nathan Kanya and the rights to Carson Rockhill on February 5, 2013. In his first season with the Ti-Cats Lawrence made an immediate impact, amassing 53 tackles, 3 special teams tackles, 1 quarterback sack, and 3 interceptions.
On February 10, 2014, Lawrence signed with the Minnesota Vikings. He was released on May 13, 2014.
Hamilton Tiger-Cats (II)
As a free-agent Lawrence signed with the Hamilton Tiger-Cats, agreeing to a three-year contract on June 1, 2014. In 2014, Lawrence played in 16 of the 18 regular season games, and both playoff gamesen route to the team's second consecutive trip to the Grey Cup. He led the team in tackles in that season, with 78; while adding 3 sacks, 2 interceptions and 1 fumble recovery. Lawrence continued his stellar play into the 2015 season, accumulating 78 tackles, 5 sacks and 2 interceptions. His performance on the field was recognized when he was named a CFL All-Star. In his fourth season with the Ti-Cats Lawrence set a career-high with 89 tackles, while also contributing 4 sacks and 1 interception for a touchdown. On January 11, 2017 Lawrence and the Ti-Cats agreed to a two-year contract extension. Lawrence was suspended for two games by the CFL for his hit to the head of Saskatchewan Roughriders quarterback Zach Collaros in his team’s 2019 season opener. During Week 14, Lawrence was fined by the CFL for uneccessary roughness, when he twisted Terry Williams' ankle. In Week 15 Lawrence was fined the maximum amount under the CBA for a late hit to the head of Eskimos quarterback Logan Kilgore.