The exception to the requirement for a search warrant to protect one’s rights against unreasonable search and seizure. If an officer has legal justification for being in a place and she spots something that is clearly suspect or proscribed, that object may be seized and introduced in a courtroom proceeding. Similarly, if the officer overhears something because it was uttered out loud so that it was overheard by an officer using normal hearing senses, that may be testified to by the officer. Additionally, use of a flashlight to make it easier to spot an object is acceptable, because it is a usual thing to do. Use of an X-ray machine, on the other hand, is unusual and, therefore, not permissible without a warrant.