The game of cat and mouse between common man and law enforcement agencies started once radar guns were used to fine people for speeding. Dale Smith from Ohio was one such person and he felt that he was unfairly given a speeding ticket; he sued his electronics background and invented the Fuzzbuster in 1968.
The in the 1970s, Cincinnati Microwave Inc. produced a different version of the Fuzzbuster and claimed that this was even better. First came the tiny passport and then the Escort.
Later Jammers were also invented; these jammers could kill the waves and prevent any speed from getting reported back to the cops.
However, the use of these detectors and certainly the jammers are illegal in many countries and only in some places it is legal. There is an argument that by using these detectors people slow down and then everyone behind also slows down leading to fewer accidents and better fuel usage. However, this falls flat with law enforcement.
To counter such radar detectors the radar detectors detector (RDD) was invented and is being used by cops in order to detect if a person has a radar detector in his vehicle. Thus the game of cat and mouse is now complete with each party trying to outwit the other. A device called as VG-2 Interceptor is the first known RDD and then further developments were done and more current RDD is the Spectre III.
If one is willing to take the risk and buy a radar detector it is better to read some of the radar detector reviews before buying them. They can also be compared and bought online. Some of the features to look out are reliability and accuracy, even if there is a false alarm it is ok but if some radar gun goes undetected then one could end up in a lot of trouble.
Happy speeding but stay safe and away from the cops.