US v. Williams: Authorities in Fairfax, Virginia were investigating a series of emails sent to a local church school which indicated the writer's desire to engage in sexual activity with some of the boys there. The investigation led to an email account in the name of Williams's wife. As a result, authorities obtained a search warrant for Williams's home, searching for evidence of Virginia offenses of sending threatening or obscene messages via computer. While conducting the search, one officer opened a lock box in Williams's garage and discovered a machine gun and silencer, neither of which, upon inspection (to determine if the gun was loaded), had a serial number. Officers also seized a DVD which, it was later revealed, contained child pornography.
Williams moved to suppress the gun, silencer, and DVD as beyond the scope of the warrant (based largely on the work of Orin Kerr, who weighs in here). The district court denied the motion and found Williams guilty (on stipulated facts) of two counts of possession of an unregistered firearm and possession of child pornography. On appeal, the Fourth Circuit affirmed the district court's denial of Williams's motion to suppress.
As to the DVD, Williams argued that when searches of computer data are at issue a traditional Fourth Amendment approach is inappropriate. Specifically, Williams argued that the search warrant did not authorize the search of every file on his computer (or related media), but only those files related to the offenses being investigated. Furthermore, a broader search for child pornography did not fit into any well established exception to the warrant requirement (i.e., plain view). The Fourth Circuit disagreed, concluding that the images on the DVD were "instrumentalities" of the Virginia offenses that were the object of the search. In the alternative, the court held that the seizure of those images was justified under plain view, as the scope of the warrant allowed investigators to open every file in order to determine its contents with regards to the offenses being investigated.
As to the machine gun, the court also concluded that the plain view exception applied, holding that the warrant allowed a search inside the lockbox for media devices that could be stored within, which would require picking up the gun and silencer to move them. The officer, once allowed to pick those items up, was entitled to inspect them for safety purposes.