Fairfax County, Va., Provides Real-Time Access to Police Data

Using an overhauled mapping app, citizens can access hundreds of police service calls, in addition to neighborhood disturbances, thefts, drug or sex offenses, and more.

by / October 7, 2014

In Fairfax County, Va., the police department already has opened up its data to residents -- with the new and improved Police Events Application, citizens can obtain real-time, mobile access to neighborhood disturbances, thefts, drug or sex offenses, and more. And the county has taken its commitment to open government a step further -- now, hundreds of new police service calls are immediately integrated into the system daily from a variety of sources, allowing the county to cut back on time spent gathering data and greatly reducing the need for support calls.

Fairfax County is among the largest counties in the nation, with more than 1 million residents, and one of its goals is to help those residents feel more at ease with access to police data. The county’s existing GIS-based Police Events Application had been in use for several years, allowing the public to search, filter and map police service calls by type, location and date, and access preliminary police investigation data from Fairfax County’s 9-1-1 call center. But with more than a half-million data points from all over the county, the data overwhelmed the existing Oracle relational database. 

“The district stations would get a lot of calls from people wanting to move to an area within the county, for example, and asking for information on police activities that had taken place around a particular address or school,” said Jim Callahan, lead application developer in the Fairfax County GIS office. “In the past, someone at the station would have to manually create a report for them. The county was looking for a way for citizens to serve themselves. The old system had also gotten very slow and was built with old technology. We were looking for a complete makeover, from how it looked to how well it performed.”

But that was no simple task. The county’s GIS database contains data from more than 800 different sources, including libraries, schools and hospitals. Most of those sources have unique schemas, making the data difficult to sort through and access. In addition, only a fraction of it was structured data available to the public (through Web applications written in JavaScript), and there was no way to exclude certain GIS datasets from unconstrained search unless they were specifically requested. This meant the existing database had to be searched layer by layer and one column at a time, making searches slow and difficult. 

The Fairfax County Department of Information Technology (DIT) tested several databases in search of the best solution, and the answer came in the form of a NoSQL database from MarkLogic. 

The new GIS database houses more than a half-million data points about police events and geography, and gives Fairfax County DIT the ability to make complicated queries. That data is now easily accessible to both county employees and county residents via the revamped Police Events Application.

“The new database gives the department the infrastructure it needed to improve query times on GIS database searches, as well as the ability to make more of that data accessible to the public,” said Callahan. 

Searches are now returned in sub-seconds, making the system much more useful. In addition, queries can be made from either a desktop computer or a mobile device. The mobile app takes advantage of location technology to help users launch a search in their immediate vicinity, if desired. 

The new database has led to a massive increase in traffic to the site and usage of the application, according to Callahan.

Today, a family moving to the county can query the database about police activity around their new neighborhood and see the requested data instantly on a map. If they are interested in a particular item, a case number comes up, and they can then call the local police station with that case number to request more details. 

“Providing the public an easy way to find this information on their own instead of requiring someone from one of the police stations to find and provide it means people working at the stations can focus on more critical job duties,” said Callahan. 

While the Police Events Application was the first to go live, Callahan said there is significant potential for the county to leverage the new database for other types of public-facing apps in the future. 

Justine Brown Contributing Writer