A couple of Tory loyalists I just spoke to – one a minister, another a PPS – said their failure to support the prime minister yesterday was primarily about the way they felt “bounced” by a sudden and ropey bill.

One Tory MP who abstained said he couldn’t get his constituency association round with such a last minute, bolt from the blue bill. A manifesto commitment, a draft bill etc, he said, and it would’ve been different.

Rebels claim the attorney-general has said in private (Dominic Grieve – an abstention last night) that he thinks the bill isn’t good law as it stands.

But there will be many motivations lurking in the grass of last night’s vote.

One PPS I spoke to sounded like he simply wanted to poke David Cameron in the eye.

One minister was particularly struck by Adam Afriyie’s unpredictable political journey. Mr Afriyie voted against gay marriage last night, but the minister said he remembered in 2005 trying to get Mr Afriyie to support the embryonic David Cameron for leader campaign. He says Mr Afriyie said he was reluctant to  sign up in the early stages of the leadership race because he was uncomfortable with David Cameron’s outspoken support for the institution of marriage which he thought was a bit old-fashioned. How times change.

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