That is a sign of corruption. I was told that by a sheriff. Great guy had a phd in law enforcement. I was told by my ex, a deputy, that she would have friends pull me over in my county. I told that to the sheriff. He pulled out his business card and told me if I get pulled over in his county to call him. He then wrote his home number on the back of the card. He said if a deputy pulls me over he would fire both of them. Then he explained to me that is a sure sign of corruption.
Later I researched it and is correct.