All posters so far make very good points.
NevadaRef reminds us that rules are in place to back us up for any decisions we do make. This is important to have in the book: the ground foundation.
Example: I am in the process of writing a 4-page document that will be the rules for touch football that I play. Some rules will be included so that in case we want to invoke them, they are there. Since it's a rec league, it's often that gentlemen agreements will override the rule, but in case of a disagreement, the rule is the sole text.
Junker provided IMO, the best first step. Many times in my career, the fact that I'm near some bru-haha (sp?) has caused things to diffuse.
mick provided the second step: to verbalize the effect (
not affect
) that the actions are having.