In the USA, background search or background check customarily refer to a search for criminal records on a particular person because criminal records are considered public information. However, a background search can involve a lot more than criminal records, for example a
complete background search
with phone number, address, criminal record check, sex offenders, terrorist watch list, address history for 30 years, age, birth dates, household members, relatives, associates, property ownership, lawsuits, marriage, divorce, bankruptcy, tax liens, and more. It's pretty scary how much information private background search companies gather about people. In the USA, anyone is allowed to run a background check on anyone else, without even telling them about it. The only restrictions are for landlords, employers, and lenders. Those 3 categories have to get the applicant's permission before running a background search. Of course, if the applicant does not give permission, he probably will be refused the job, loan, or apartment.