I'm sure we've discussed this before, but I need some clarification on basket interference, NFHS rules:

4.6.1 says it's basket interference if a player touches the ball or any part of the basket while the ball is on or within the basket. I presume that includes the backboard.

High school rec league yesterday, a boy was making a point of slamming the backboard while the opponent went for a layup. This would be BI, right? What if it occured BEFORE the ball is 'on or within' the basket? No call? thanks!

NFHS
 

No, it is not BI. The backboard is not part of the basket. See rule 1-10.

If there's no attempt to block the shot and he's just slapping it, it would be a T.

Found it. . . .
 

OK, got it. . .

3.6.b. . . .while a try or tap is in flight or is touching the backboard or is in the basket or in the cylinder above the basket, intentionally slap or strike the backboard or cause the ring to vibrate.

Well, there's your mistake.

SECTION 10 BASKET SIZE, MATERIAL
ART. 1 . . . Each basket shall consist of a single metal ring, 18 inches in inside diameter, its flange and braces, and a white-cord 12-mesh net, 15 to 18 inches in length, suspended from beneath the ring.

The basket is the ring, flange and net. Backboard not included. ;)