San Diego area residents had an impoverished view of crime in their city; the official crime maps only showed a few weeks of incidents, and the local statistics covered entire neighborhoods, neglecting to consider the difference in time of day or commercial crime versus residential crime. Worse, the data that could answer these questions were not available, and the agency that controlled the data responded to requests either with refusals or quotes of very high fees.
Over the course of six months and 50 emails, we negotiated with the agency that held the crime data, eventually getting 6 years of data for a fee of $134. Then, working though our non profit project, the San Diego Regional Data Library, we led volunteers in visualization projects to produce time series and heat maps, allowing citizens to understand how crime incidents vary with time of day and fine grained locations. Then, we posted the datasets and visualizations publicly as a resource for many subsequent local and national research projects.