Pass Interference on an Illegal Forward Pass

[OverAndBack]

We had a spirited debate about this in our association meeting tonight.

Can you have pass interference on an illegal forward pass?

The example that people kept coming up with was an intentionally-grounded pass, but with what would normally be pass interference on the other side of the field. We seemed to reach a consensus that if the contact on the other side of the field didn't have an effect on the play, no call. If one of the wings thought it might have made it so the receiver couldn't get into the area of the pass and that's why there was no receiver in the area, then it would be called (the referee would need help on this, as he'd be staying with the passer after the pass).

If I'm missing anything on that, JRut will jump in, he was in the meeting.

But my question (which I didn't ask because we were getting bogged down) was what about another illegal forward pass?

Scenario:

First and 10 from B's 45 yard line. A1 drops back and rolls right. He runs just pass the line of scrimmage and lets fly downfield. As the ball is in the air, B2 interferes with A2 and the pass is incomplete.

Does the illegal forward pass negate the interference?

Or is it offsetting fouls?

Just thought I'd throw it out to everybody to see what the opinions are.