Michigan has now adopted the 85% law for speed limits. The speed limit is not based on what the cities or counties set. Rather, it is based on the speed that 85% of the motorist drive at.

The idea is simple. 85% of all motorist will drive at a speed that they feel is safe and appropriate even if that speed is higher than what is posted. The other 15% will drive at a higher and unsafe speed than the norm.

So, the speed for any given road will be determined by the speed of 85% of the motorists. Therefore, cities and counties are to post speed limits based on the 85% rule rather than arbitrarily imposing speed limits.

And while the 85% rule is now law, it will be a while yet before it will be successfully used to beat a speeding ticket.