DETROIT — Like most Americans, the drivers of Detroit are required to carry auto insurance whenever they get behind the wheel, but many law-abiding residents can’t afford the Motor City’s highest-in-the-nation auto premiums, which top $5,000 a year in some neighborhoods.

So fully half of Detroit drivers do what’s known locally as "driving dirty" — taking to the streets without any coverage. It’s practically a tradition here.

Now Mayor Mike Duggan is trying to do something about the high insurance costs based on concerns that they are deterring new residents and investment from coming to Detroit as it rebuilds after emerging from bankruptcy last year.