From the Chicago Tribune's Chris Kuc:

Blackhawks forward Andrew Shaw could face discipline from the NHL for the possible use of a homophobic slur during Game 4 of the Western Conference quarterfinals Tuesday night at the United Center.

After being assessed an interference penalty late in the Blues’ 4-3 victory, Shaw was yelling at officials while seated in the penalty box and video of the incident appeared to show him using a homophobic slur.

After the game, Shaw was asked if he had used a slur.

“I mean, emotions are high, I really don’t know what’s said,” Shaw said. “I was obviously upset with the call being that late in the game (as) it doesn’t give us a chance to tie it up.”

When asked again if he used the slur, Shaw replied: “Like I just said, I can repeat myself for you. Emotions were high. I don’t know what was said. Obviously, I was upset with the call. It was late in the game like that. I wasn’t happy with the call.”

Continued, and this happened after Shaw's penalty was over: