What should have happened here?

[mbyron]

Originally Posted by Reffing Rev.

Well,

Live ball foul for illegal motion against A.

Dead ball foul for personal foul againt B.

Play ended short of line to gain.

Team B has the choice of accepting or declining the penalty for A's foul.
Take the penalty it will 5 yards agaisnt A and then 15 yards against B, if the distance is enough for a first down, then first down for A, if not then repeat 4th down.
Decline the penalty and it will be B's fall 15 yards behind were the play ended for the personal foul.

Right, though this should be K and R.

If the officials presented the options to B correctly, it should have gone something like this: "You can accept the penalty for IM and give them a first down after we enforce the penalty for the late hit, or you can decline their penalty, keep the ball, and start 1st and 10 from 15 yards back."

R probably kept the ball by declining the penalty. If that's what happened, it was not "waved off" (as the OP suggests).

[Rich]

We had a play on Friday night where a dead ball USC foul changed the decision of team B.

3rd down and about 10. There's a run up the middle that left A about a yard short of the LTG. When A's captain asked who the foul was on, I told him and the offending player flipped and drew 2 flags (one from me and one from the U). One foul, of course.

So, without the USC it would've been 4th and 1 and I'm pretty sure B would've accepted the penalty as it would've made it about 3rd and 20. But with the USC, they were able to decline the penalty and make it 4th and 16. Had A reached the LTG on the play, B would've had to accept both penalties to keep it 3rd and long.

All pretty straight-forward penalty enforcement (once we verified that A was short of the LTG on the 3rd down play) and it seemed pretty easy when I presented those options to the coach, but without having some simple principles down pat, it would've been more confusing.

[Robert Goodman]

Originally Posted by mbyron

Right, though this should be K and R.

There being no kick, there was no K or R. It was clear from the original post which team was A because the live ball foul was for illegal motion.

If the officials presented the options to B correctly, it should have gone something like this: "You can accept the penalty for IM and give them a first down after we enforce the penalty for the late hit,

Only if that distance was sufficient for first down.

or you can decline their penalty, keep the ball, and start 1st and 10 from 15 yards back."

R probably kept the ball by declining the penalty. If that's what happened, it was not "waved off" (as the OP suggests).

Probably. Possibly the original poster didn't see the option being presented to B's captain.