By which I don't mean that members of the party are more transphobic than the average person, or that their representatives are.
What I mean is that
1) They have an upcoming election (in May)
2) They need to get 50% of the voters to vote for them so that they can get a majority and try and push through a referendum
3) Enough of their voters are against transphobia to affect that election
4) Enough of their MPs and MSPs say things which are (at the very least interpreted as) transphobic to drive away some of the membership.
The SNP are held together by a defining principle, to gain independence for Scotland from the UK. All other things fall by the wayside. But not everyone who votes SNP will put up with absolutely anything the SNP comes up with, so there's a constant tension, as they try to keep a majority onside.
In the past, transphobia is one of those things that's been seen as too divisive to actually deal with. There are too many members/representatives who don't see trans people as being the gender they declare themselves to be, and there was no point fighting it out.
But the last few days have seen enough people make a big fuss, and start to leave the party, that Nicola Sturgeon has stood up and said that she is utterly against transphobia.
Vitally, the SNPs National Executive Council has been asked to come up with a definition of transphobia. Because there's no point them declaring that they're not going to tolerate transphobia unless there's a clear line that tells people what behaviour is and isn't okay.
And it's when we see that definition that we'll know whether the SNP really means it, or if they're just trying to muddy the waters to hold things together until after the elections.
I have a terrible worry that they'll hold off on publishing a definition until after the elections. If they aren't going to do that then they need to get them out very soon to avoid any negative reactions/schism carrying over into the election period.
(The SNP isn't the only pro-independence party in Scotland of course, the Greens are too and are very clearly pro trans rights.)
Original post on Dreamwidth - there are comments there.