I was travelling to Tombstone, AZ (North) from Sierra Vista, AZ along Charleston Road. The normal speed limit is posted as 50 Miles Per Hour and has been so in this area for at least the past 25 years. All of a sudden, an abviously brand new sign of "40 Miles Per Hour" appeared on my side of the road just south of the Escapule Road Turn-off. Two Cochise County Sheriff Office patrol cars with lights flashing were sitting on a bend no more than 100 feet into the "40 MPH" posting. One of them "lite me up" and gave me a ticket for driving "56 MPH" in a 40 MPH zone. I asked him "why is there no "reduced spped ahead sign" and received no answer. Suspicious, I walked back to his car where he was writing the ticket and asked him to show me the radar registered speed. He stated, "by law I do not have to let you see it". Sure enough the speed was blazing in red numerals as "52". The officer not only committed highway robbery, but lied about the speed. Despite my protest, he did not change the "56" on my ticket. Watch out Sierra Vistans, the worst form of theft, that by so-called "law enforcement" is out there and wants your wallet. It will cost me over $150.00 for this theft unless I attend the "Traffic School" and "humble myself".