I had not applied my mind, I confess, to the mechanisms for correcting what I perceived to be the danger, but I am content if I have satisfactorily set out that danger, and if the Minister will consider it. This is not an oppositional point: it is being raised in order to prevent him from inadvertently going beyond his stated purpose.

A person is obliged to provide material. Even if it contains only the name and address, the very existence of something called ''material'', particularly when produced from a particular place, might be important evidentially, and be compellable under the clause. That is not what the Minister wants to get his hands on.