Cuando el gato va a sus devociones, bailan los ratones, could be translated with the english idiom “When the cat’s away the mice will play!”
It means that in the absence of a controlling entity, subordinates will take advantage of circumstances.
Cuando el gato va a sus devociones, ¡bailan los ratones!
Other Proverbs
A fleeing enemy, silver bridge ( A enemigo que huye puente de plata)
Who grasps at too much loses everything
Appetite comes with eating
“Be more apañao’ that a peseta”