Freeman played four seasons of collegiate football for the Mary Hardin-Baylor Crusaders and was twice named a D3football.com All-American, including being honored as the 2007 D3football.com Defensive Player of the Year. When he graduated he left as the school's all-time leading tackler. In his senior year he had 59 tackles, 18 tackles for a loss, and six quarterback sacks.
Professional career
Tennessee Titans
Jerrell Freeman declared himself eligible for the 2008 NFL Draft. Although he was not drafted he was signed by the Tennessee Titans immediately following the conclusion of the draft. He became the first Mary Hardin-Baylor Crusader to be offered an NFL contract. Jerrell Freeman was released by the Titans prior to the start of the 2008 NFL season.
Saskatchewan Roughriders
In March 2009 Freeman signed with the Saskatchewan Roughriders of the CFL. In the 2009 CFL season Jerrell Freeman was used primarily as a special teams tackler, recording a team high 25 special teams tackles. He was nominated as the team's Most Outstanding Rookie. In his second season with the Riders Freeman saw more time as a regular linebacker. He made the starting lineup for one game in the regular season and started in two playoff games and the Grey Cup. Jerrell Freeman won CFL Defensive Player of the Week honors in week 7 after recording 3 sacks against the BC Lions. He led the team in sacks by the end of the season with 7. The 2011 season was a breakout year for Freeman. Freeman lead the CFL in tackles with 105. Freeman won CFL Defensive Player of the Week in week 10 and earned CFL Defensive Player of the Month for the month of September.
Indianapolis Colts
On January 16, 2012, Freeman announced that he had signed a contract with the Indianapolis Colts of the NFL. In Week 1 against the Chicago Bears, Freeman returned a Jay Cutler interception for a touchdown in the first quarter. Freeman had an outstanding first season with the Colts finishing with 145 tackles and 2 sacks. His 145 tackles was the fifth highest total in the league. Freeman won the AFC Defensive Player of the Week award for his performance in a 23–7 win over the Kansas City Chiefs on December 22, 2013. He finished the game with 7 tackles, 1 quarterback sack, 1 forced fumble, 1 interception, and 3 passes defended. He was also initially credited with 2 interceptions, but one was later adjusted to a strip/sack for teammate Robert Mathis and a fumble recovery for Freeman. In 2014, he recorded 95 combined tackles, 6 pass deflections, and 1 forced fumble in 12 games played. On March 5, 2015, the Colts made a qualifying offer to Freeman, which he signed on April 27.
Chicago Bears
On March 12, 2016, Freeman signed a three-year, $12 million contract with the Chicago Bears. He was suspended four games on November 21, 2016 for violating the league's performance-enhancing drug policy. On September 12, 2017, Freeman was placed on injured reserve after sustaining a pectoral injury and a concussion in Week 1 against the Atlanta Falcons. On October 30, the Chicago Bears announced that Freeman had been suspended for 10 games for violating the NFL's performance-enhancing drug policy for a second time. Freeman apologized for the suspension, adding that his playing career might be in jeopardy due to a head injury and memory loss. On May 2, 2018, Freeman announced his retirement from the NFL. He was suspended an additional two years by the NFL on May 11, 2018, after failing a third drug test.
