Thanks for the background, I’m not familiar with UK’s regulation on telcos.

I stand corrected, this isn’t like wiretap as the article mention Communication Data (CD) is metadata rather than content. It’s still very intrusive as it show who is talking to who, when, and possibily where (location is metadata).

The scale is still surprising, what kind of crime is London police investigating at a scale of 700k (or even 100k) a year ? It still beaches privacy so it should be proportional. It make sense to make access to metadata a bit easier than metadata+content. That’s food for thought for citizens and lawmakers.