tenho a certeza de que isso nao exista em ingles; por isso pode dar uma traducao assim

my sugg: add a translator note explaining details of the tactic

If I understand correctly - um grupo de pessoas empurrando em portao de uma vez = a group of people (prisoners, in this case) storming the door.

"Os agentes penitenciários estão aprendendo como evitar o cavalo doido. O cavalo doido é o método preferido pelos presos para começar uma rebelião" - might be - "The prison guards are learning how to avoid prisoners from storming the doors. Storming the doors is a preferred method among prisoners for starting a riot."

A stampede is an act of mass impulse among herd animals or a crowd of people in which the herd (or crowd) collectively begins running with no clear direction or purpose. Stampedes are believed to originate from biological responses in the brains and endocrine systems of herd animals. The response is believed to have evolved to help animals escape predators.