Administrative Searches. Search warrants are generally required for administrative fire, health, or safety inspections of residential or private commercial property. Even where a warrant is not required, there must be some opportunity for precompliance review before a neutral decisionmaker, unless there is consent or an exigent circumstance. The probable cause requirement for administrative warrants is less stringent than for criminal investigations because the privacy interests at stake are deemed less important. An administrative search is valid if there is evidence of an existing violation or if the search is pursuant to a general, neutral administrative plan. A warrant is not required if there are exigent circumstances or there is valid consent to the search.

An administrative search is invalid if its sole or primary purpose is to look for evidence of criminal activity. However, a combination of administrative and investigatory purposes is acceptable, so officials may still conduct an administrative search if they have some suspicion of criminal activity. Also, if a valid administrative search discloses evidence of criminal activity, the evidence may be seized under the plain view exception to the warrant requirement.

The Supreme Court has upheld warrantless administrative searches of closely or “pervasively” regulated businesses. The justification for this exception to the warrant requirement is that individuals doing business in a closely regulated industry have a reduced expectation of privacy. Whether an industry is closely regulated depends on the “pervasiveness and regularity of the ... regulation” and the effect of such regulation on the privacy expectations of persons doing business in the industry. A warrantless administrative search of a closely regulated business is reasonable if: (1) there is a substantial state interest behind the regulatory scheme; (2) the search is necessary to further that scheme; and (3) the authorizing statute is an adequate substitute for the warrant requirement because it gives notice to business owners and limits the discretion of those performing the search.