According to this article, Republican legislators are open to other churches who want to establish their own internal police departments. Why?:
“They will conduct their own investigations,” explained (Rep. Connie) Rowe. “They will conduct their own security. They will make their own arrests and instead of calling on the local law enforcement agency to take over the particular situation they're trying to control, they will do that themselves. All they will utilize from their other law enforcement agencies is their lock up facilities.”The church police will be directly answerable to church leadership.
It makes you wonder how safe an individual church is that they actually feel the need to call on the police for security or internal investigations. I understand that stuff happens. There were two church-based arrests in Iowa last month involving mentally disturbed individuals who were out of control. But those incidents are actually very rare. I cannot imagine why any church would need its own police force.