Meaning of the word "when the cat's away, the mice will play" in English

What does "when the cat's away, the mice will play" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

when the cat's away, the mice will play

US /wen ðə kæts əˈweɪ, ðə maɪs wɪl pleɪ/
UK /wen ðə kæts əˈweɪ, ðə maɪs wɪl pleɪ/
"when the cat's away, the mice will play" picture

Idiom

people will behave badly or as they please when the person in authority is not present

Example:
The teacher left the classroom for five minutes and the students started shouting; when the cat's away, the mice will play.
As soon as the boss went on vacation, the office staff spent all day chatting; when the cat's away, the mice will play.