It's not a specific rule reference, but if possible you might want to try and explain that Officials are not "the enemy", that the main difference between a coaches perspective and an officials perspective is that, for the game to work, we MUST consider the interests of both teams equally.
Coaches and officials are different parts of the same effort to produce a successful game. As different as Sales and Human Resources, we each have different roles in reaching the same objective, sometimes we provide valuable assistance to each other, sometimes we may seem to step on each other's toes but our objectives should be parallel and point to a similar goal.
You might also remind your coaches audience, that whomever and wherever the notion started that screaming and publicly demeaning an official, will ultimately benefit your position has about as much chance of helping you as screaming and publicly demeaning your spouse, and very often produces the exact same results.