Earlier quoted context omitted.
I feel like this is a part of UK's ongoing effort to make ubiquitous surveillance a completely normal thing and have the citizens accept it as such. It's not creepy and disturbing, it's actually normal and should be celebrated!
I think this would only be legal in the UK if it was made clear that the communications were subject to monitoring; see https://ico.org.uk/media/for-organisations/documents/1066/em... pp58 onwards. I can see it being argued both ways; transcripts of Bloomberg chat were a key part of the LIBOR scandal, for example. And I can also see there being some need to monitor internal chat in case it's used for unacceptable pur…
You don't want simple monitoring. You want data stored in a way it can be checked after a complaint has been filed but only then. Encrypt it with something which requires one or multiple keys so random IT people don't have access to it. Log every access so an audit can be done.
Treat it like medical data should be treated.