Over-rule your partner?

[BayStateRef]

A1 bringing ball across division line under moderate pressure. I am trail (2-whistle), across the court with clear view of the play. Ball and one foot are in frontcourt. One foot has never left back-court. A1 then dribbles ball again in backcourt.

My partner blows the whistle from the lead and calls a backcourt violation.

He is wrong. He is calling out of his area. I have nothing but court between me and the play and have been watching (and counting) the entire time.

So what do you do? Get together with him and let him know one foot never left the backcourt? Do nothing and talk to him after the game?