He went on to become a star at Northeastern University, where he finished his career with the single-season defense scoring record for the Huskies as a First Team All-American and Hobey Baker Award finalist.

Despite spending nearly half the season in the minor leagues, he led all rookie NHL defensemen in scoring.

Prior to the 2006–07 NHL season, Fahey was traded with Alexander Korolyuk to the New Jersey Devils for Vladimir Malakhov and a conditional first-round pick.

[1] On July 27, 2007, Fahey signed with the Chicago Blackhawks and spent the full year with the Rockford IceHogs of the AHL.

On July 6, 2010, after two seasons with Krefeld, Fahey signed a one-year contract with rival DEL team Thomas Sabo Ice Tigers.