WHITEHALL, Mich. — A former Scout leader from Whitehall has been sentenced to more than 17 years in prison for sexually exploiting minors. Investigators say Robert Alan Mark, 59, used hidden cameras to record minor girls undressing and using the bathroom over the course of a decade. Mark served as a leader in Boy Scouts, now known as Scouting America. Investigators found that over 10 years, Mark used hidden cameras to record minor females undressed, showering and using the bathroom. Hidden cameras were found in his bathroom, a bedroom in his home and a tent.