Last month, when talking about the big Californian case about Proposition 8, I mentioned the unexploded bomb created by articles 2, 3 and 4 of Directive 2004/38 on the free movement rights of EU citizens and their families: they give an unconditional right of free movement within Europe not only to every EU citizen but to his or her spouse – a term which is undefined.

I don’t think anyone intended it, and I’m not sure many people are aware of the issue, but I think read purposively (as it must be) the Directive extends to same-sex spouses married in countries like the Netherlands – thus forcing the UK to recognise such marriages at least for EU law purposes. I’m okay with that – I’m in favour of gay marriage. But I can imagine some people won’t be okay with it – and this might become a big row.

It may be that the issue never arises in litigation – if the gay spouses of EU citizens are given all the rights that are enjoyed by British married couples. I think the government must be crossing its fingers and hoping that happens, so that the problem is resolved silently. But if a married gay couple from Europe is not treated equally with traditional married couples within the scope of EU law – for instance in terms of employment rights, benefits, housing and so on, as they affect free movement – then the equal treatment provision in article 24 of the Directive may allow them to make a legal claim which will draw attention to all this.

Anyway, the point that interests me is that, in its guidance on implementing the Directive adopted recently (I’m grateful to EU law blog for drawing attention to them) the Commission has been silent on the question of who is a spouse. Not by accident, perhaps.