[SEMW]

That was the European Court of Human Rights. It's not a 'top EU court', or an EU court of any sort. It's a body of the Council of Europe, which is an entirely different institution (with a much larger international membership than the EU). It enforces the European Convention on Human Rights.

(the EU does requires members to be CoE members, and so there were some people suggesting that after leaving the EU the UK might also leave the CoE - possibly including theresa may, I haven't checked - but that doesn't currently seem likely to happen)

The EU Charter of Fundamental Rights is definitely a thing - basically a copy of the ECHR into EU law - but it's only applicable (1) to actions of EU institutions, (2) as a restriction on EU legistation, and (3) as an obligation on member states _when interpreting / implementing EU law_. It has no relevance to UK law other than that. (And what little relevance it would have had to the UK was further weakened since they had a partial opt-out to it that tried to get rid of the last of those for the UK!).

The cases about UK surveillance legislation (eg [0]) were all ECtHR, not CJEU.

[0] https://hudoc.echr.coe.int/app/conversion/pdf/?library=ECHR&...