The Lord Speaker, Baroness D’Souza, said the vote against Lord Dear’s anti-equal marriage bill amendment was a “massive, massive defeat” for him, but warned that further “ping-pong” debate on various issues within the bill would be imminent.

The Baroness told The House Magazine that the House of Lords had become more “confident” when criticising legislation approved by the House of Commons.

One example of this, she argued, was the fierce debate sparked by Lord Dear’s proposed amendment to the Marriage (Same Sex Couples) Bill, which proposed not to give the bill a further reading.

The ‘fatal’ amendment to deny the bill its second reading was tabled earlier this month, but was defeated, with the Lords voting 390 votes to 148 in favour of the bill.

The amendment went against the convention of the Lords not to veto decisions made in the Commons, said Baroness D’Souza.

“There’s no question over the years that our scrutiny function has become more, let me say, confident.”

She said the 390 votes against Lord Dear’s amendment were “a massive, massive defeat for him”, adding a large part of this could be put down to peers feeling it was “entirely wrong” to cut down a bill with such large support in the Commons. Some of those who voted against the amendment may, in fact, oppose the same-sex marriage bill’s content.

This may lead to the bill facing further difficulties in the House of Lords, Baroness D’Souza predicted.

“I don’t think you’ll quite see those sort of [big] majorities for the bill now that we are into Committee, Report and Third Reading, because there will be a lot of amendments. There are people who are very against some aspects of it and there may well be ping-pong. It’s a very contentious issue,” she said.

The second day of Committee debate on the bill took place on Wednesday, with further debate scheduled for tomorrow.