A background check

plural of background investigation

A journalist investigating a single topic of interest, often involving crime or corruption.

The domestic intelligence and security service of the United States, which simultaneously serves as its primary federal law enforcement organization.

In Finland: the National Bureau of Investigation (Finland) / In the Philippines: the National Bureau of Investigation (Philippines)

(law) A team formed jointly by national law enforcement agencies to investigate cross-border crime.

plural of patient under investigation

(public health)

In terms of, or by means of, investigation.