I would just add a few words to what Lord Tyler has written about the power to subpoena witnesses. I was asked yesterday by a journalist whether a select committee had the power to require someone who was not a UK citizen to appear before it. I pointed out that select committees in the Commons are normally vested with the power to ‘send for persons, papers and records’. The Culture, Media and Sport Committee, like other departmental select committees, has this power. This means they can summons to attend anyone within the jurisdiction of Parliament, in other words within the UK. There are certain exceptions, but nationality by itself is not relevant in this context. The only foreign nationals who cannot be required to attend are people such as ambassadors.
Anyone failing to comply with a summons can be reported by the committee in a special report to the House. The House can then determine whether failure to comply with the summons is a contempt of the House. If it so decides, it can punish those guilty of contempt, including by fining or even imprisoning them.
When Rupert and James Murdoch failed to accept the invitation of the Culture, Media and Sport Committee to give evidence to it next week, it exercised its power to issue a summons. Both have complied with that summons and will now be appearing before the committee on Tuesday.