The
internal affairs (
United States terminology) refers to a division of a
law enforcement agency that investigates incidents and plausible suspicions of
lawbreaking and professional
misconduct attributed to officers on the force. Internal affairs can also refer to cases of misconduct and
criminal behavior involving police officers. In different systems, internal affairs can go by other names such as "Internal Investigations Division" (usually referred to as 'IID'), "professional standards," "
inspectorate general",
Office of Professional Responsibility or similar. Non-internal affairs officers often derisively refer to the departments as the "rat squad". Due to the sensitive nature of this responsibility, in many departments, officers employed in an internal affairs unit are not in a
detective command, but report directly to the agency's chief, or to a board of civilian police commissioners.