This study shows just how powerful the city's property tax data can be - Philly


Jan. 12, 2016 8:01 am

This study shows just how powerful the city’s property tax data can be

Former Philadelphia Chief Data Officer Mark Headd used the city's newly-released property tax balance data to see how many tax delinquents got city permits in the last two years.

The city's recent release of property tax data opened up a bunch of doors.

(Apartment building in Philadelphia, Pennsylvania by Jon Bilous via Shutterstock)

When the City of Philadelphia released property tax data mere days before Mayor Michael Nutter left office, Mark Headd got right to work.

Now that he had access to the data, Headd, Philadelphia’s first Chief Data Officer, wanted to do an analysis. How many tax delinquents did the city give permits to in the last two years?

Headd doesn’t live in Philadelphia anymore, doesn’t work for city government. He left for Syracuse shortly after he left City Hall. But that didn’t matter. This analysis was important to him.

You see, Headd did a similar analysis while he was still working for the city, just 18 months ago. He did it to prove a point. He wanted to show the importance of releasing property tax balance data, of releasing the data in a machine-readable format, because not everyone in City Hall agreed that it was the right move — and Headd was frustrated by that. He left city government shortly after.

And now, here he was, with the dataset he had fought so hard to get released. (Headd championed the release as a “huge win for the open data team in Philly.”) He finished the analysis in a little over a week, working throughout the New Year holiday, and posted his findings on GitHub.

“The project,” he wrote to us, “was a bit of a catharsis for me.”

In his analysis, Headd found that about 4 percent of the more than 20,000 properties that owed more than $1,000 in property taxes in 2014 had gotten permits from the city.

See the analysis

While the city hasn’t yet done a full inspection of the analysis, Rebecca Swanson of the city’s Department of Licenses & Inspections said that it’s important to remember that safety is L&I’s primary concern. So L&I would never deny a tax delinquent a building permit if it were a matter of making the property safe.

“If we refused to issue a permit to repair an unsafe condition because of a tax delinquency, this would negatively impact public safety,” Swanson wrote in an email.


(For this reason, Headd later updated his analysis to take into account L&I violations.)

Swanson also noted that some tax delinquents may be involved in a payment plan or another type of agreement with the Revenue Department and this analysis doesn’t account for that.

L&I plans to “audit the findings to determine whether there is a systematic issue that needs to be addressed,” she said.

We couldn’t get comment from anyone at the Revenue Department because Commissioner Clarena Tolson no longer heads the department (she’s now the deputy managing director for infrastructure and transportation) and her replacement, Commissioner Frank Breslin, has not yet started.

Maybe this analysis will bring to light a way for the city to collect more back taxes. Or maybe it won’t. But what really feels important is that this data release has started a conversation. That the dataset allows people outside of government to do these kinds of projects. That the release of this data means that city agencies, like the Revenue Department and L&I, could share data more easily to do their jobs better.

And since Chief Data Officer Tim Wisniewski will remain in office under Mayor Jim Kenney, that might mean more of the same.

Juliana Reyes

Juliana Reyes became's associate editor after reporting on the Philadelphia tech scene for four years. She's co-president of the Asian American Journalists Association Philadelphia chapter and a two-time Philadelphia News Award winner for "Community Reporting of the Year." The Bryn Mawr College grad lives in West Philly, likes her food spicy and wears jumpsuits often.


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