State v. Dwight M. Sanders, 2008 WI 85, affirming as modified, 2007 WI App 174
For Sanders: Patrick M. Donnelly, SPD, Madison Appellate
¶32 The protective sweep doctrine applies once law enforcement officers are inside an area, including a home. Once inside an area a law enforcement officer may perform a warrantless “protective sweep,” that is, “a quick and limited search of premises, incident to an arrest and conducted to protect the safety of police officers or others.”  Under Buie, a law enforcement officer is justified in performing a warrantless protective sweep when the officer possesses “a reasonable belief based on specific and articulable facts which, taken together with the rational inferences from those facts, reasonably warranted the officer in believing that the area swept harbored an individual posing a danger to the officer or others.”  Because the protective sweep exception authorizes only a limited intrusion, Buie requires the officer to have only reasonable suspicion that the area poses a danger to the officer or others; the test is not probable cause.
¶33 The protective sweep extends “to a cursory inspection of those spaces where a person may be found”  and may last “no longer than is necessary to dispel the reasonable suspicion of danger and in any event no longer than it takes to complete the arrest and depart the premises.”