background check
noun [ C ]
ukus(also background investigation) HR
a check of what a person has done in the past, usually as part of the process of deciding whether or not to employ them:
Applicants can expect a thorough background check for trustworthiness in handling sensitive materials.
conduct a background check on sb The airport finished conducting thorough background checks on 11,000 airport personnel who have access to secure areas.
A criminal background check showed he had convictions but offered no details on what they were for.