Surprisingly quick for his size, his tendency to be flamboyant following a successful play placed him as a person of concern for officials.

During the 2011 BCS National Championship Game against the Oregon Ducks, Fairley had five tackles, a sack, and a forced fumble.

Only four days after the 2011 BCS National Championship Game, Fairley decided to forgo his final year of eligibility, entering the 2011 NFL draft.

However, on October 26, 2014, Fairley sustained a Medial collateral ligament sprain against the Atlanta Falcons at Wembley Stadium in London.

[15][16] Fairley played in 15 games for the Rams in 2015 along their defensive line rotation and recorded 29 tackles (18 solo), a split sack, a pass defended, and one fumble recovery.

[17][19] After recording career-highs in tackles and sacks in 2016, Fairley signed a four-year, $30 million contract extension with the Saints during the 2017 off-season.

[20] On June 26, 2017, the Saints placed Fairley on the reserve/non-football-illness list regarding a lingering heart condition, ending his 2017 season.

[25] On May 27, 2012, Fairley was arrested by Alabama State Troopers for driving under the influence and attempting to elude police.

[27][28] On December 1, 2018, Fairley was arrested on criminal menacing charges when he allegedly threatened a person with a gun.