Conspiracy of silence (expression)

The expression "conspiracy of silence" is used to describe a situation in which many people agree to keep something a secret, usually because they are afraid. This can happen when someone does something wrong and other people don't want to get in trouble, so they all pretend like it didn't happen. It can also be used to describe times when people of a certain group, like a community or a family, come together and agree not to talk about a bad thing that happened.