Do the reasons you give for the formation of police departments also apply to the increase in the prison population? What was imprisonment and punishment like before the 20th century?
]]>You’re right that modern professionalized police forces are a relatively new invention. (The Boston Police Department, usually cited as the oldest professional police force in the U.S.A., dates to 1854, although there was a small organized daytime patrol before that which was established in 1838.) Prior to that most law enforcement was carried out either by a few appointed officers (sheriffs and marshals, in the U.S.), by officially-organized posses, or by individual-level or mob informal enforcement. Larger cities did often hire on night watches to stand guard at checkpoints or make patrols around a relatively limited circuit.
Most cities developed a professionalized police force much later than that, even. I would argue that the fact that your average small town maintains a government police force these days is still largely a function of state and federal government subsidies aimed at putting cops on the streets.
I’m sure that population growth had something to do with this; but I think that what had a lot more to do with it were (1) increasing demands on the government to act as an instrument of permanent social control (first by breaking Irish heads, later by attacking vagrants
and people walking while black, then the War on Drug-users, etc.), where before it had acted mostly as an occasional agent of terror (so, not constant patrols and harassment, but rather the occasional massive reprisal); (2) political centralization and the spread of state and federal subsidies for their favored sort of local good government
policies; and also (3) the emergence of professionalized, civil service models of government, with the consequent increases in government employment at all levels and the increasing insistence on professionalization, and on autonomous executive departments with independent hiring power and bureaucratic management.