Andrew Henderson watched as Ramsey County sheriff's deputies frisked a bloody-faced man outside his Little Canada apartment building. Paramedics then loaded the man, a stranger to Henderson, into an ambulance. Henderson, 28, took out his small handheld video camera and began recording. It's something he does regularly with law enforcement. But what happened next was different. The deputy, Jacqueline Muellner, approached him and snatched the camera from his hand, Henderson said. "We'll just take this for evidence," Muellner said. Their voices were recorded on Henderson's cellphone as they spoke, and Henderson provided a copy of the audio file to the...