Dr Julian Lewis: On a point of order, Mr Speaker. You may remember the second time I raised as a point of order the difficulties of the Select Committee on Defence in getting the national security adviser to give us evidence in relation to the national security capability review that is currently under way. You expressed yourself in very strong terms on 27 November, when I last raised this subject. Since then, this stand-off has not made any progress, but I have discovered one thing – [Interruption.]

[Mr Speaker: Order. This is a serious matter. I know that colleagues are waiting for the next business, but previous points of order were heard with courtesy. The right hon. Gentleman must be heard. This is an important matter and I want to be able to give him an informed reply.]

Dr Lewis: I have discovered a matter that gives a fresh perspective on the claim that the national security adviser need only give evidence to the Joint Committee on the National Security Strategy and not, for example, to the Defence Committee – namely, that I now see from the recently published annual report of the Intelligence and Security Committee that as recently as last year the previous national security adviser gave evidence, in his capacity as NSA, to that Committee in addition to the Joint Committee. When precedent has so clearly established ​the fact that the NSA does speak to other Committees when it suits him, what more can I do to get him to speak to my Committee?

[Mr Speaker: I am grateful to the right hon. Gentleman for his point of order. I think I am right in saying that it is open to him to require the attendance of the said witness. It would be prudent of him to be sure in his own mind that he has the support of his Committee in making any such direction or requirement. Moreover – I am sorry that these are muddy waters – giving effect to such a requirement if it is not adhered to would very likely require the approval of the House. This is therefore a matter that can take a little time, and it is not completely straightforward or immediate in terms of effect, but it is open to the right hon. Gentleman to persist. I note what he said about previous examples of the national security adviser appearing in front of the Defence Committee rather than in front of, or in addition to, other Committees, and that is certainly a powerful argument in his arsenal.

I know that sometimes Governments are inclined to invoke the Osmotherly rules as justification for saying that one official can and another official cannot appear in front of a Committee. My response to that, on behalf of Parliament, is to say that the Osmotherly rules are very much a Government creation. This House has never endorsed or recognised the Osmotherly rules. They are, perhaps, a matter of great importance in the minds of Ministers, and in particular, I fancy, in the minds of officials; they are not important in my mind at all.]