The FBI investigated former Milwaukee County Sheriff David Clarke over a January incident with a passenger on a plane, according to a recently unsealed search warrant first spotted by the Detroit News. Clarke, a vocal Trump surrogate, had a minor disagreement with fellow passenger Dan Black on a Milwaukee-bound plane. Clarke texted one of his officers, asking him to detain Black when the plane landed. "Just a field interview, no arrest unless he becomes an asshole with your guys," Clarke texted, according to the FBI affidavit. Six officers and two police dogs met Black at the plane's exit, Black wrote in an official complaint. The affidavit also reveals that Clarke emailed subordinates asking them to post "memes and messages" including one calling Black a "snowflake" on the official Milwaukee County Sheriff's Facebook page.