While you don't have to cite every source of data or create a research paper with bibliography and footnotes, it is important to cite any experts you quote and to credit published reports from which you take data. Add just a few resources and citations if they are available. For example, if you are writing about prostitution in your city, add some statistics about prostitution in general.
Be sure when you cite national statistics to link them to the case in your own community. In the above example, you might say: “Here in City, State, the police department receives no special budget allocation for battling prostitution. Instead, it works with courts, social-service agencies, and others to share and reduce costs. It has also streamlined the arrest process to reduce the amount of time officers spend completing paperwork. Last year's 300 arrests cost the city only $10,000 (after fines were paid); police officers spent approximately fourteen hours per arrest.”