Yup, that's Justin Bieber. He played a troubled teen on the season 11 premiere of CSI.
Added:

CSI Season 11 Episode 1 Quotes

Haskell: I want Ray to live a long time so he thinks of me every time he unzips his pants
Brass: Yeah, he will remember what a putz you are.

Brass: You know what this button does.
Ray: Morphine clouds my thinking.