The Marriage (Same Sex Couples) Bill has pretty much finished its passage through the House of Lords. Not only was the majority for the principle of gay marriage higher in the Lords than in the Commons (225 in the Commons, 242 in the Lords), but pressure from peers meant the government conceded changes to the bill including on the subject of humanist weddings in England and Wales and equalising pensions for gay couples.
The bill was not amended at all during its passage through the Commons, but has been subject to extensive amendment by the government in the Lords. Aside from the two big changes mentioned above, most amendments have been fixing the drafting of the bill.
The Commons and the Lords have both spent about 48 hours debating the bill, suggesting there’s not been significant filibustering either (allowed in the rules of the House of Lords, which doesn’t allow for bill debates to be guillotined).
This is perhaps surprising because often second chambers can be seen as the preserve of (small-c) conservative forces with the express purpose of thwarting progressive initiatives; from the foundation of the Fifth Republic until 2011, the French Senate was dominated by conservatives; the House of Lords had, from the early 19th Century until the close of the 20th, been dominated by small- and big-c conservatives.
Even after the end of the Conservative majority in the House of Lords, there was staunch opposition to equalising the age of consent for gays in 2000 and to the creation of civil partnerships for gays in 2004.
Given its reputation, there was widespread anxiety over whether the Lords would gut gay marriage, but instead it’s made the legislation fairer and arguably more progressive. Since 2004, hundreds of peers have been appointed and hundreds of the older peers have died. The House of Lords is undergoing a generational change and will only get more comfortable with gay rights.