My case is unique. I was a college professor at Ohio University, coming from UC Berkeley. I taught Sociology and Criminology. At the time (the early 70's) there were no authors writing about police who had actually served as peace officers. I decided to leave academics and do a few years (it turned out to be 40!) and return to academics with some substantial insights. I was the valedictorian and president of my police academy. Since I wanted to understand the profession, I volunteered for any assignment or position I could get. Eventually I worked my way up the ranks, including serving as a Chief of Police for ten years.
There is no clear explanation for what happened, except to say that I continued to teach police and a variety of forms of criminal justice, but from a different vantage point.