During a basketball freethrow, what happens if you try to distract the shooter?

Question

During a freethrow shot in Basketball after a foul, players stand in front of the freethrow shooter. What happens if those players try messing with the freethrow shooter? Like yelling "BRICK" right as he shoots, or waving their arms like a lunatic, or doing some crazy tiktok dance, etc..

To be clear, I'm talking about non-physical meddling. And assuming that there's obviously a line that can be crossed (e.g. screaming "BLOODY MURDER" at the top of your lungs), around where is that line, and why don't we see players pushing up against it?

Answer 1

Both waving arms and yelling at the shooter are specifically disallowed.

From the NBA Rules: rule 9 I f:

During all free throw attempts, no opponent in the game shall disconcert the shooter once the ball is placed at his disposal. The following are acts of disconcertion:

• Raising his arms when positioned on the lane line on a free throw which will not remain in play,

• Waving his arms or making a sudden movement when in the visual field of the shooter during any free throw attempt,

• Talking to the free throw shooter or talking in a loud disruptive manner during any free throw

• Entering the lane and continuing to move during any free throw

PENALTY: No penalty is assessed if the free throw is successful. A substitute free throw will be administered if the attempt is unsuccessful.

Answer 2

While fans can distract, anybody associated with a basketball team cannot.

This happened with Devin Booker. After complaining to the ref against the Raptors, he had the Bulls mascot removed after a similar distraction.

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