What authority does a third party have to consent to a search warrantless search?

Common authority to consent to a search rests on mutual use of the property by a person having joint access or control for most purposes. United States v. Matlock, 415 U.S. 164, 171 n. 7 (1974); see United States v. Dearing, 9 F.3d 1428, 1429 (9th Cir.1993). A warrantless search is justified even if the third party does not possess actual authority to consent where the police have reasonable grounds to believe that the consentor has authority to consent. See Illinois v. Rodriguez, 497 U.S. 177, 188-89 (1990); see also United States v. Welch, 4 F.3d 761, 764-65 (9th Cir.1993). Whether a person voluntarily consented to a search depends on the totality of the circumstances and is reviewed for clear error. United States v. Kim, 25 F.3d 1426, 1431-32 (9th Cir.), cert. denied, 115 S.Ct. 607 (1994).