well as a comment - whilst Andie waits for an answer that May Never Come -
we could rehearse the shameful episode of the Cambridge 5
[ anthony blunt and all that stuff ]
bright cambridge lads thinking stalinism was a better go than parliamentary democracy. O dear god ....
or the IRA who inilftrated the Met
the secret police car number plates were 'unlisted' and all the spies had to do was remember the numbers of those car comign back as unlisted ( hence no key strokes and no audit trail)
It went to the house of Lords on whether looking at a screen could be a terrorist act [ or did they have to do something else like note it down]
or indeed ELi Cohen
https://en.wikipedia.org/wiki/Eli_Cohen
who said he was one of them - but wasnt - he was one of the other ....
any sign of an answer andie ?
If anyone can give me a ref ( case no) on that I would be grateful