My Lords, I shall briefly respond to the points that have been made. I am grateful to the noble Lord, Lord Beith, for amplifying the case that his noble friend made in introducing the amendment. In the end, we come back to the point that the noble Lord, Lord Carlile, has just articulated. We are talking here about the proper, legitimate use of the powers that the Bill contains, with robust oversight and mechanisms for redress built in, and the Investigatory Powers Commissioner is indeed an important safeguard in that context.
We are absolutely on board with the proposition that where an innocent person has been completely wrongly subject to the use of the investigatory powers—that is, where a serious error has occurred—there is no
argument that that person should be informed. However, I submit that one cannot talk in the abstract about someone who has been “wrongly investigated”, which I think was the phrase used by the noble Lord, Lord Beith. You can be wrongly investigated if you are completely innocent, but you can also be wrongly investigated if there is perhaps not enough to pin on you as the culprit in a particular case but you might nevertheless, subject to further evidence, be implicated in a serious crime or a threat to national security. So we have to be clear about our terms in this context.
I come back to the fact that there are issues of principle and practice here that make this particular amendment unworkable. I also take on board the very good point made by the noble and learned Lord, Lord Hope, that it is not just an individual who could react to the news that they had been investigated in a way that would frustrate law enforcement agencies or intelligence services but a whole group of people. That in turn could affect national security, or indeed the conduct of criminals, much more widely.