Gov. Mitch Daniels (R), in announcing Miller's resignation, said Miller "has been an exceptional public servant."
"Indiana farmers, flood victims, motorists and taxpayers in general all have benefited from his hard work and leadership in three important capacities," Daniels said in a statement. "I also know him to be a devoted father to three children, including one saved from cancer by Riley Children's Hospital, for which Andy in turn has raised substantial funds in gratitude."
He added that "if things are as reported, the law must be respected, but either way this is just an extremely sad situation."
Police say Miller came into the men's room of a downtown hotel while police were conducting a sting. According to the police report, an undercover officer followed Miller into the restroom, where Miller allegedly went into a stall, dropped his pants and began masturbating. The officer stood in front of the stall which, according to the report, had only chest-high doors. Miller allegedly invited the officer to touch him.
Miller, who according to the BMV web site is married with three children, asked if the officer was married. When he said yes, Miller said he was too and told him it was OK, according to police. When the officer expressed nervousness about being caught, Miller allegedly asked if he wanted to go somewhere else.
The officer then left the restroom. When Miller followed, he was arrested.
Miller was named chief of the BMV in January 2009. He recently accepted an international customer service award for his work at the department, where he reportedly drastically cut wait times.
Before that, he was director of the Office of Disaster Recovery, and before that, Indiana's first director of agriculture, a position Daniels appointed him to in 2005.