A federal appeals court found the Los Angeles County Sheriff's Department violated the constitutional rights of a California man when they used an administrative warrant to gather evidence for a criminal investigation.

The U.S. Court of Appeals for the Ninth Circuit affirmed a district court order granting a Lancaster man's motion to suppress evidence seized by the sheriff's department during a protective sweep they made while accompanying city officials during a search over suspected violations of civil property codes.

Judge Wallace Tashima of the U.S. Court of Appeals for the Ninth Circuit, who authored the opinion, and U.S. District Judge M. Douglas Harpool of the Western District of Missouri, sitting by designation, held that the LASD's execution of the warrant was unreasonable under the Fourth Amendment since the "primary purpose" of the investigation was to gather information on a criminal case involving illegal possession of firearms and methamphetamines.

Judge Jay Bybee, however, dissented, arguing that the court shouldn't have focused on the intent of the sweep, but "whether LASD's protective sweep and ensuing inspection of Grey's house was an 'unreasonable' search."

Franz Grey was a "difficult neighbor" who surrounded his property with tarps, electrical wiring and a "camera mounted on a 30-foot pole," according to the opinion. His neighbors told police that they witnessed him fire an AK-47 in the air, possess a large amount of methamphetamine and operate an unlawful auto repair business on the property. During a search over alleged building code violations, the officer in charge of the criminal investigation and nine other deputies spent 15 to 20 minutes sweeping Grey's home to ensure it was safe for the city to execute its warrant over the building code violations.

The majority disagreed with the government's arguments that the presence of the officers was "harmless," because the sweep would have occurred regardless of the deputies alleged efforts to build a criminal case against Grey.

"Under the Fourth Amendment, reasonableness is determined by assessing the degree to which a search or seizure 'intrudes upon an individual's privacy,'" they wrote. They assert that Grey would not have been arrested before the search. "Nor would nine armed deputies have descended on Grey's home. And the deputies' 'protective sweep' would not have lasted 15 to 20 minutes, perhaps longer," the judges found.

In his dissent, Bybee said the opinion is "contrary to basic Fourth Amendment principles."

"Given the inspection warrant from a California Superior Court, which authorized LASD to accompany the housing inspectors, the deputies would have entered Grey's house regardless of their subjective motivations," he wrote. "Instead, the correct inquiry is whether, once inside the home, the deputies' actions exceeded the permissible scope of a protective sweep."