The app has inherently limited accuracy and I think the algorithm it's using would likely flag anyone who goes anywhere near an event where a large number of people end up testing positive. It can't really tell the difference between, say, people attending a mass superspreading rave and mingling with contagious attendees with no protection, and police officers in PPE rounding up attendees who've been infected at the event but aren't contagious yet. It's just a fundamental limitation of using an automated app. This probably isn't a huge problem most of the time, but it seems like police using the app could rapidly deplete the ability to actually enforce Covid restrictions.

Couldn't the officers just ignore the app recommendation, but still use it? If they don't use it at all, they become breaks in the transmission graph.

In other words: if I was infected and attended a rave, a policeman interacted with me, and you interacted with that policeman two days later, you'd probably want to know about that fact and consider self-quarantining.

Yes, but I would hope that police are more aware of the situation and taking protective measures compared with say 2 people getting together for coffee. If this is the case the definition of contact needs to be different

> This seems like the equivalent of saying that we can't have carbon monoxide alarms in this building because they keep going off.

The comparison works if you add that the building is always filled with CO and that this is a known fact and that people in it are pros and take the appropriate measures. In such case, CO alarms are just noise.

Police evolve in a high risk environment and have procedure against that. Because of that and the security requirements of the Police, it has simply been concluded that the downsides of installing a third party tracker on a police phone outweighed the upsides.