Reports are beginning to circulate about requirements to collect personal information for use in manual contact tracing. As many people have noted, manual contact tracing will require privacy trade offs. The question is how big a trade off and what do we get in exchange. 1/

What we get is a lot. As @EmilyGurley3---who is leading an online training at Johns Hopkins for contact tracers (great idea!)---has put it, "Contact tracers are in part detective, part therapist and part social worker.” https://www.washingtonpost.com/health/2020/05/11/this-course-will-train-an-army-contact-tracers-you-can-take-it-too/ 2/

Thousands of trained contact tracers, with access to rapid testing and backed (when needed) by quarantine authority, would make a big difference in containing coronavirus according to just about every expert I've read or talked to. 3/

To do this big job, contact tracers will need access to sensitive personal information. Health status, medical history, recent contacts, maybe location information, and so on. We will need to trust them like nurses, doctors, and other healthcare professionals. 4/

Meanwhile, if people are to congregate indoors around strangers, contact tracers may sometimes need to know who was at a restaurant, store, or other location. Presumably this animates @GovInslee's decision to require a log of customers when businesses reopen. 5/

Which brings me to two crucial points: First, whether manual contact tracing has inevitable privacy trade offs has zero bearing on whether exposure notification apps are a good idea---they continue not to be. 6/

And second, while you cannot entirely avoid privacy harms connected to manual contact tracing, you can and definitely should mitigate them! Plans, like Washington's, that don't expressly address privacy and security should be criticized on that basis. 7/

It's fair to ask:

why *every* diner needs to submit contact information, not just one person making a reservation or paying

why 30 days is the right length of retention & whether the business *must* destroy the information after 30 days

how the information will be secured

8/

It's fair to ask:

who can access this information and for what purpose (e.g., the police)

whether the business itself can use the information and how

what the penalties are for violations, like the Subway employee who asked a customer out

/9

This is all Privacy 101, and there is just no reason to sacrifice privacy mitigation at the alter of the pandemic. But again, none of this has anything to do with the relative merits of exposure notification apps on your phone because: manual contact tracing probably works. 10/10