Liles was then invited and selected to play in the U.S. National Team Development Program based in Ann Arbor, Michigan, in which he was an integral part of the blueline in both the under-17s and −18 squads.

Alongside teammate Brad Fast, Liles formed a star offensive duo among Spartan defensemen and in his sophomore year, he scored 25 points in 42 contests to be named to the All-CCHA Second Team.

[citation needed] During his senior season with the Spartans, Liles again led the team in scoring, registering 50 points in just 39 games while helping Michigan State to a 23–14–2 record.

Signing an amateur try-out contract the following day with Colorado's American Hockey League (AHL) affiliate, the Hershey Bears, Liles made his professional debut against the Grand Rapids Griffins on March 30 and played in ten games to end the 2002–03 season.

[6] During the NHL lockout the next season, Liles enjoyed a brief stint in the German Deutsche Eishockey Liga (DEL) for the Iserlohn Roosters, playing in 17 contests and scoring 11 points.

[9] After suffering the disappointment of failing to qualify for the Stanley Cup playoffs for the first time in Avalanche History, Liles helped lead the team return to the post-season in 2007–08.

[12] Transitioning into a senior role for the Colorado defense, Liles scored his 50th career goal against the Toronto Maple Leafs on January 29, 2009, to become only the fifth defender in Quebec/Colorado history to achieve the feat.

[13] Hampered by a re-occurring shoulder injury midway through the 2009–10 season, Liles also struggled with returning to form and was a healthy scratch for a brief period for the first time in his NHL career.

On January 1, 2014, Liles was traded to the Carolina Hurricanes, along with Toronto prospect Dennis Robertson, in exchange for defenseman Tim Gleason,[19] just minutes before the former was scheduled to play for the Maple Leafs in the 2014 NHL Winter Classic against the Detroit Red Wings.

[23] Initially, Liles was selected to play for Team USA in the 2000 World Junior Championships in Umeå, Sweden, but suffered an injured shoulder in the last minute of the last exhibition game to rule him out of the tournament.

[24] During the 2004–05 NHL lockout, Liles made his international debut when he was recalled prior to his European stint with the DEL's Islerhohn Roosters as an injury replacement for Hal Gill for the 2004 World Cup.

[26] Liles' place was retained within Team USA when he was named, alongside future teammate Jordan Leopold, as a part of the young core of the squad to appear at the 2005 World Championships.