46-year-old Gary Cottrell was arrested Friday morning.
He is accused of making high interest loans and at times using force to try and collect the money.
Cottrell had already lost his job with the force after being arrested two years ago for insurance fraud.
Police say one of his clients was 18th District Officer Cheryl Stephens.
Stephens is also facing charges, she is accused of lying to a grand jury about not being charged interest on her loans.