The CDC Paid for Location Data From Millions of Phones Collected by Safegraph

Joseph Cox, Vice:

The Centers for Disease Control and Prevention (CDC) bought access to location data harvested from tens of millions of phones in the United States to perform analysis of compliance with curfews, track patterns of people visiting K-12 schools, and specifically monitor the effectiveness of policy in the Navajo Nation, according to CDC documents obtained by Motherboard. The documents also show that although the CDC used COVID-19 as a reason to buy access to the data more quickly, it intended to use it for more general CDC purposes.

Location data is information on a device’s location sourced from the phone, which can then show where a person lives, works, and where they went. The sort of data the CDC bought was aggregated — meaning it was designed to follow trends that emerge from the movements of groups of people — but researchers have repeatedly raised concerns with how location data can be deanonymized and used to track specific people.

Remember, during the early days of the pandemic, when the Washington Post published an article chastising Apple and Google for not providing health organizations full access to users’ physical locations? In the time since it was published, the two companies released their jointly-developed exposure notification framework which, depending on where you live, has either been somewhat beneficial or mostly inconsequential. Perhaps unsurprisingly, regions with more consistent messaging and better privacy regulations seemed to find it more useful than places where there were multiple competing crappy apps.

The reason I bring that up is because it turns out a new app that invades your privacy in the way the Post seemed to want was unnecessary when a bunch of other apps on your phone do that job just fine. And, for the record, that is terrible.

In a context vacuum, it would be better if health agencies were able to collect physical locations in a regulated and safe way for all kinds of diseases. But there have been at least stories about wild overreach during this pandemic alone: this one, in which the CDC wanted location data for all sorts of uses beyond contact tracing, and Singapore’s acknowledgement that data from its TraceTogether app — not based on the Apple–Google framework — was made available to police. These episodes do not engender confidence.

Also — and I could write these words for any of the number of posts I have published about the data broker economy — it is super weird how this data can be purchased by just about anyone. Any number of apps on our phones report our location to hundreds of these companies we have never heard of, and then a government agency or a media organization or some dude can just buy it in ostensibly anonymized form. This is the totally legal but horrific present.

Reports like these underscore how frustrating it was to see the misplaced privacy panic over stuff like the Apple–Google framework or digital vaccine passports. Those systems were generally designed to require minimal information, report as little externally as possible, and use good encryption for communications. Meanwhile, the CDC can just click “add to cart” on the location of millions of phones.