A video captured the angry crowd as it swarmed a football field to protest a penalty flag. A man grabbed the referee from behind and body-slammed him onto the ground. The players, who looked on, stunned, were 13 years old. The assailant was a parent at his son’s youth football game in Albuquerque.

The New Mexico Young America Football League responded by banning the entire team for the rest of the season. Parents there, as in many states, are required to adhere to a “Parents Code of Conduct” that includes abiding by statements such as “I will be in control of my emotions” and “I will remember that the game is for our youth — not adults.” That pact had been broken.