They did the same thing in Georgia with the “Ludowici Law’. Locals could not give a ticket for less than ten miles over and the highway patrol generally would not.
I once visited a friend who was locked up in Ludowici. It was not even up to the standards of Mayberry. Two decrepit cells with a master padlock to hold them shut.
If I remember correctly , about 60 years ago, Ludowici was known as the home of "What's my fine," because of it's notorious speed trap. -Tom