After the game -- a 110-108 Dallas win -- Smith denied what replays clearly revealed.
"No, your eyes were playing tricks on you," he said with a laugh, repeating the refrain a questioner used. "You're reaching for that one. I [already] got fined once for that s---."
Video showed Smith tugging at Carter's headband with 10:54 left in the fourth quarter after the veteran guard hit 3-pointers on consecutive Mavericks possessions.
Carter seemed to laugh it off.
The NBA might not find it as amusing. Smith was fined $50,000 by the league in early January for attempting to untie two of his opponents' shoelaces.
He was later benched for one game by Knicks coach Mike Woodson for his shoelace antics.