Research and write up your findings, explaining why police/public ratios vary so much around the United States.
What are the arguments that are used? And, what is their validity?
Resources:
http://www.governing.com/gov-data/safety-justice/police-officers-per-capita-rates-employment-for-citydepartments.html
https://www.bjs.gov/content/pub/pdf/csllea08.pdf