He was considered one of the top linebacker prospects for the 2010 NFL draft,[2] and was selected with the 79th overall pick by the San Diego Chargers.

As a junior in 2004, he had 1,504 rushing yards and 22 touchdowns, leading Del Campo to a 9–2 record and the Capital Athletic League championship.

In the 2010 NFL draft, the San Diego Chargers traded up 12 spots to select the Butler in the third round.

[4] Butler suffered a season-ending injury prior to the start of his rookie season as he tore his left Achilles tendon during a pass rush drill.

He had a stellar game against the Kansas City Chiefs on September 30, where he caught a tipped off ball and returned the interception for a 21-yard touchdown.

Butler played 13 games, missing 3 with a groin injury, managing to make 84 tackles, half a sack, 1 interception, and a fumble recovery.

In the wild card round vs the Cincinnati Bengals, Butler stripped running back Giovani Bernard from behind, which was ruled a fumble and recovered by the Chargers.

Butler was an impending free agent for the 2014 NFL season, but on February 28, 2014, he announced on Twitter that he would be staying with the Chargers on a multi-year deal.