App-based Contact Tracing to fix the police brutality pandemic?

I have spent some time researching the value (if any) of app-based contact tracing (see App-based Contact Tracing is a Distraction to fight the COVID-19 pandemic. I also keep reading about the police brutality pandemic.

This made me click: can we use app-based contact tracing for better police accountability?

How it would work

Police officers would constantly broadcast a unique pseudonym over Bluetooth. This can be done through their bodycams or an improved version of their badge.

People would have an app installed on their phone (even better, pre-installed on every phone) that keeps recording the pseudonyms it receives.

This way, all interaction with the police can be traced.

When there is a “questionable interaction”, the people involved can be identified and more information can be gathered, e.g. footage from the body cam.

How this is different from app-based contact tracing

  • This model is asymmetric. Pseudonyms are generated by members of the police forces and collected by “civilians”.
  • For COVID-19, a trigger is when someone reports they have in infected with the virus. Here, a trigger is when someone reports a “questionable interaction”.


  • This only works for close-contact interactions. If a bullet (rubber or metal) gets wrongly fired, this is not captured by the system.
  • This assumes good coverage on both sides: enough “devices” broadcasting pseudonyms and enough phones recording them.
  • There are ways to prevent the Bluetooth signal from being transmitted.
  • Trolling is another big risk
    • people reporting a problem for any encounter they have
    • people harvesting pseudonyms
  • There are some privacy issues, e.g. for undercover activities, conversation with informants, etc.

Most if not all of these problems are solvable. I am sure that the great minds who came up with COVID-19 app-based contact tracing could repurpose their work for a different kind of pandemic.

Crazy idea?

1 Like

This is a good article about body cams and why they don’t work as well as they should.

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