What is going on with Philly’s police district numbers?

Normally, lists and maps are designed to tame chaos and put the world in order. Not so with police districts in Philadelphia. Looking up the 21 districts on the Philadelphia Police Department’s website may only confuse you. South Philly, for example, encompasses Districts 1, 3, and 17, whereas the central part of the city is divided into 6, 9, and 22. And the districts seem to randomly skip numbers, going from 3 to 5 and from 9 to 12. An enigmatic order, if there’s any order to it at all.

So what’s going on with the district numbers, a reader asked through Curious Philly, The Inquirer’s forum for questions about the city and region. What’s the logic behind these numbers? “And what’s up with the airport as the 77th police district,” the reader wanted to know.

Here’s what we found out about how Philly’s police districts are numbered.

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The districts have roots in the 1854 Act of Consolidation, which united Philadelphia city and the county under a joint government and, according to the police department, enlarged the territory to 129½ square miles and about half a million inhabitants. This called for a bigger police force. The law also made boundaries for the city’s police districts and election wards the same. The mayor was granted the right to appoint one lieutenant and two sergeants for each district.

Roughly a century later, after a 1948 public investigation shed light on corruption in PPD’s detective and vice bureaus, Philly’s police districts were reorganized. To detach the force from political influence, Commissioner Thomas J. Gibbons “consolidated the police districts and redrew their boundaries to separate them from ward lines,” the department said in a statement.

Officers are assigned to set districts and normally don’t switch unless they get transferred.

At this time, there are 21 police districts in Philly: three in the south (1, 3, 17), four in the southwest (12, 16, 18, 19), three central (6, 9, 22), three in the east (24, 25, 26), four in the northeast (2, 7, 8, 15) and four in the northwest (5, 14, 35, 39). There’s also the 77th district: the airport.

The explanation for omitted numbers is surprisingly simple: Several former districts got absorbed into others. The 4th District, for example, was consolidated into the 3rd District, the 23rd into the 22nd.

Any missing numbers were once active districts, but were shut down.

For the PPD, district numbers are key to their everyday policing: “All of the patrol districts generate district control numbers for assignments, incidents, and other type of service provided by the police.” They’re equivalent to any kind of serial number, allowing police to track incidents and follow assignments.

In some places like New York, police districts are called precincts. The difference in name again roots in Philadelphia’s Act of Consolidation, which established districts, not precincts. But whatever you call them, they can share one significant quality: The NYPD’s precincts are oddly numbered too, going from 1 to 5, 63 to 66, 94 to 100.

While the Act of Consolidation has been the foundation for any police district math so far, it has nothing to do with the airport’s number. The fact that PHL comes in as the 77th District derives from the police department’s daily attendance report. The report is designed to keep track of police department personnel, show how long each employee worked, and organize absences. In the report, every district, unit, and some of the divisions has a four-digit numerical code, the PPD said. Actually, the airport’s daily attendance report code is 7700, but to keep things simple, it’s abbreviated to 77.