[darrenoc]

It may be reasonable, but it's very poor optics. It makes it seem like they are trying to coverup any possible COVID exposures within the force.

[mytailorisrich]

The police cannot create security risks for the sake of placating social media users in search of conspiracy theories.

[Daviey]

The app is said to be secure and privacy preserving, so is it both secure and privacy preserving? If it is, why aren't the police routinely installing it?

If the reason is that due to coming into contact with lots of people would skew the results, then this would be manipulation of the data.

There is no good answer for this current position.