The New York Jets selected Slauson with their sixth round pick in the 2009 NFL Draft. The Jets offensive line coach Bill Callahan previously coached Slauson at Nebraska and considered him versatile, athletic, and durable. Slauson was signed to a four-year deal by the team in May. Slauson would appear in three regular season games in 2009 playing at the guard and center positions respectively.
Following the team's selection of Vladimir Ducasse in the 2010 NBFL Draft, the Jets would release veteran guard Alan Faneca. During the team's training camp sessions, Slauson battled Ducasse to replace Faneca. On September 9, 2010, Slauson would be named the team's starting left guard.
Slauson became the subject of criticism after utilizing a cut block against Brian Cushing that resulted in Cushing tearing his ACL on October 8, 2012. The play was considered legal by USA Today as both were within three yards of the line of scrimmage where an offensive lineman is allowed to low block a defensive player; the Houston Chronicle contended that the block itself was legal but the location of the block was not. Cushing, when asked about the play, stated "It's football. It's part of the game...it happened to me, and I've been on the other side of that, so I know how it goes." Slauson was fined $10,000 by the league after they determined that he used an illegal peel-back block.
On March 29, 2013, Slauson signed a one-year deal with the Chicago Bears. On January 2, 2014, Slauson was re-signed by the Bears to a four-year contract. On January 24, Slauson was named to the USA Today All-Joe Team.
In 2014, against the New England Patriots, Slauson tore his right pectoral muscle, and was ruled out for the rest of the season. On April 7, 2015, Slauson was awarded the Ed Block Courage Award.
On May 1, 2016, Slauson was released by the Bears.
Slauson signed a two-year contract with the San Diego Chargers on May 7, 2016.
Slauson was born in Cincinnati, OH to Nancy and Robert Slauson and attended and played football at Colerain High School before graduating from Air Academy High School in Colorado Springs, Colorado. From a young age, Slauson was diagnosed with stuttering, a speech disorder that occurs primarily when he is placed in unfamiliar situations. Slauson has two other brothers, Nick and Chris, as well as a sister, Alli.
Slauson is married to Cami, and the couple have a son, Montgomery James.
Slauson is a nephew of Jim Thurber, known best for his appearances on Discovery's TV show "Gold Rush".