Schwarzenegger told Newsweek Magazine he was helping a friend when he commuted the sentence of Esteban Nunez from 16 years to seven.
Nunez pleaded guilty in the 2008 stabbing death of a San Diego college student, 22-year-old Luis Santos.
Schwarzenegger commuted Nunez's sentence just one day before leaving office, angering Santos' family and prosecutors.
In the interview, Schwarzenegger told the reporter, "I happen to know the kid really well. I don't apologize about it...There's criticism out there. I think it's just because of our working relationship and all that. It maybe was kind of saying, 'That's why he did it.' Well, hello! I mean, of course you help a friend."