Legal Definitions - informer

Definition: An informer is someone who provides information to authorities about illegal or criminal activities. They can also be a private citizen who brings a penal action to recover a penalty.

For example, if someone witnesses a crime and reports it to the police, they are an informer. Another example is a private citizen who sues an offender for a penalty before any criminal liability can attach.

The term "common informer" is also used to refer to a private citizen who brings a penal action to recover a penalty.

The informer's privilege is a legal protection that allows informers to keep their identity confidential in certain situations.