What are situations where a particular group is thought to be a danger or menace to society

Moral panics.

Explanation:

A moral panic is a sense of fear among many people that something or someone evil endangers the security of society.

A moral panic occurs when an event, person or group of people are portrayed as a menace to societal beliefs and values. It´s the case the belief in the widespread ritual abuse of women and children by satanic cults.

maybe you need to work on the pipes in the house. i am just saying this because you did not give any details.