While MPs were debating single-sex marriage, the House of Lords was busy causing trouble for the Prime Minister by beginning the process of putting some of Lord Leveson’s proposals for press regulation into effect.

The Lords voted to add an amendment to the Defamation Bill which would set up an official press watchdog recognised by the courts.

Film producer David Puttnam, a Labour peer, proposed the amendment. Midland peers Lord Fowler, the former Conservative MP for Sutton Coldfield, and Lady Boothroyd, the former Labour and later independent MP for West Bromwich, spoke in favour.

The Bill (and it’s actually a Government Bill) as amended would put one of Lord Leveson’s most important recommendations into effect. It would set out what a press regulator should look like – for example, by stating that no serving newspaper editors should sit on the board.

Newspapers themselves would then be expected to create the regulator. However, a commission established by the Lord Chief Justice would then decide whether the regulator met the criteria set out in statute (here, the Lords’ amendment differs from Lord Leveson, who wanted broadcasting watchdog Ofcom to make the decision).

Once the new regulator had been approved by the Lord Chief Justice, judges would be free to impose extra damages on newspapers which refused to join and were successfully sued. Courts would even be able to impose extra costs on newspapers which won cases – if they refused to join the regulator.

As a result, while newspapers would not actually be forced to accept the authority of the regulator, they’d have a strong incentive to do so.

Lord Fowler said he backed the amendment partly because the Government has been dragging its heels doing anything about Lord Leveson’s report – which indeed it has.

He said: “The present way of dealing with the Leveson proposals is woefully inadequate. It has brought nothing forward, although everyone at the time said how urgent it was to make progress.”