One of the big points of contention in last month's European elections was the extent to which UK law was being drawn up in Brussels. In the televised debates that preceded the election, UKIP's Nigel Farage claimed that 75% of UK law came from the EU, while Lib Dem leader Nick Clegg said it was just 7% - a claim which he later retracted in the second debate.
Full Fact said at the time that merely counting laws isn't very revealing without also thinking about the impact that these laws have. It's also not a straightforward calculation - the House of Commons Library had produced an analysis in 2010 that suggested that "it is possible to justify any measure between 15% and 50% or thereabouts".
Given the recent interest in the topic, the Library have now updated this estimate. Not much has changed: the Library now says that it's possible to justify any figure between 15% and 55%.
But in a blog post, it expands on some of the difficulties with trying to estimate proportions in this way. While all regulations from Brussels are implemented in law across member states, this doesn't mean that they all have implications in every country:
"We do not know, for example, how many regulations have direct application in the UK — olive and tobacco growing regulations are unlikely to have much impact here, but the UK implements such regulations along with olive and tobacco-growing Member States."
It's also equally difficult to judge the 'soft' power that the EU might exert on UK law, where statements, guidelines or reports from the continent may prompt British legislators to act even before a formal regulation has been issued.
While the Library's analysis is the best we have on the topic, the quick answer we can take is its point that:
"In short, neither of them is right and the actual figure is probably somewhere between the two."
We've updated our Spotlight on the topic to include this latest analysis.