Lotsa people are ditching trailers cheap that don't meet the new codes. You can update one if you like, otherwise, law in Michigan as of October 2005 is that any trailer with a GVWR OVER 1,500 lbs MUST have brakes at every wheel. And there is no grandfather clause on this. The actual law was passed back in the 90s, with Oct 2005 being the deadline for compliance.
Strangely enough, compression brakes (like on a uhaul) are still allowed.