The modern professional police force is probably one of Britain's most significant exports. In little over a century, Britain went from having a largely amateur and local law enforcement system to the type of police force we still recognize today. The first modern police force of its kind, it has become the model which has been copied and adapted across the world. This is not a story of unbroken progress. Newer methods of policing challenged English ideas of liberty and were greeted with distrust. Over time changing social conditions, particularly with the rise of large industrial cities, led...