Well, I don't know how it works in the EU, but here in the U.S. there is very little transparency in the intelligence community, and the population has no say whatsoever as to how agencies like the C.I.A. operate. They basically operate under an "it's only a crime if you get caught" philosophy, and the public is only aware of what is going on when there is a public snafu or details leak out many years later.
Considering how much the MI5 seems to operate as underhandedly as the C.I.A., it doesn't seem that far fetched that they have a spying operation that is much bigger in scope than you might imagine.
Considering how much the MI5 seems to operate as underhandedly as the C.I.A., it doesn't seem that far fetched that they have a spying operation that is much bigger in scope than you might imagine.