Which of the following is NOT a circumstance under which a warrantless search can be conducted?

A warrantless search refers to a search conducted by law enforcement without a warrant, and there are specific circumstances under which such searches can be legally justified. These include situations where consent is given, where there is an imminent public danger that requires swift action, and hot pursuit, which involves chasing a suspect into a private area without a warrant due to exigent circumstances.

Routine investigation does not fit into the legal exceptions that allow for warrantless searches. This type of investigation typically requires a warrant because it doesn't involve immediate threats or the need for rapid law enforcement action. The legal framework emphasizes that while the police have the authority to investigate, they must do so with respect for constitutional protections, which is why routine investigations lack the exigent circumstances that would justify bypassing a warrant.

Understanding this distinction is crucial for recognizing the balance between law enforcement duties and protecting individual rights.