How much of our law is made in Brussels?

Unhelpfully, it depends on what you count as “law”.

“Laws are like sausages,” as Otto von Bismarck never said: “it is better not to see them being made.” Well, those in the Brexit camp disagree. They have long questioned the content of those mysterious frankfurters churned out by the European Union, and have their stomachs set on pure, juicy Cumberlands processed right under our noses.

The first problem is working out how much of our law is made in Brussels rather than our own courts. Like most arguments about the EU involving numbers, the claims and counterclaims vary so wildly that they cease to have much meaning. The live television debate in 2015 with Nigel Farage and Nick Clegg demonstrated this: Farage insisted that 75 per cent of UK laws are made by the EU, while Clegg said the figure was 7 per cent. It doesn’t help matters that the House of Commons Library has warned that “there is no totally accurate, rational or useful way of calculating the percentage of national laws based on or influenced by the EU”.

The latest claim from the Leave campaign is that roughly two-thirds of UK law is made by the European Union. The pro-Brexit campaign group Business for Britain has made what it calls a “definitive” calculation of 64.7 per cent.

But is that true? Unhelpfully, it depends on what you count as “law”. If you’re looking at just acts of parliament (statutes) and statutory instruments (which are directives issued by ministers to flesh out existing statutes), then the figure is about 13 per cent, according to House of Commons Library research. This percentage is an average of how much UK legislation was passed to implement EU law or other EU obligations in the period from 1993 to 2014.

That proportion does increase significantly when you add the dreaded EU regulations. You know the ones: responsible for all sorts of abominations from straightening bananas to disempowering vacuum cleaners. Regulations apply automatically in all EU member states. We can also add EU directives to this – one of which suggested in 2013 that “jam” be redefined to include only products with more than 60 per cent sugar. As business secretary, Vince Cable fended off this horror, which would have left anything with a sugar content of between 51 and 59 per cent with no legal name. (As the Guardian noted, “The regulations have created what the famously dour Cable has described, in a rare moment of humour, as a ‘no jams land’.”)

If we take EU regulations and directives into account, then yes, it does start to look as if up to 65 per cent of our legislation comes from Brussels. But this figure is based on counting every law passed by the European Commission between 1993 and 2014: all 49,699 of them. Plenty of these have been dropped, replaced or rendered redundant. It is thought the total number of EU laws in force is less than half that figure (22,398, according to March 2015 reports). And many of these – measuring the pungency of olive oil, tobacco growing guidelines – are not relevant to British farmers or manufacturers.

Taking regulations into account, the Commons Library has conceded that it is possible to justify any figure between 15 and 55 per cent. So, everyone is right.

Besides gleefully drawing attention to the loopiest rules, Brexiters argue that there is a democratic deficit in having our laws made in Brussels. Although our MEPs get a say in the standard legislative process, they are not held to account in Britain by their opponents and the media in the same way as MPs. Ukip MEPs in particular take pride in failing to turn up to European parliamentary debates and committee meetings.

Among Eurosceptics, the most hated law of all is the Human Rights Act. They claim that it “protects” terrorists and criminals. Yet this is not an EU issue. The act simply incorporates the Convention on Human Rights adopted by the Council of Europe after the Second World War: it’s nothing to do with the EU. The UK parliament passed the act independently in 1998.

So yes, a significant proportion of our law is affected by the EU. But calculating just how much is a worthless exercise, partly because much of the legislation would have been implemented – or even initiated – by the UK anyway, and partly because not every law has an equal impact. We may be British, but it’s time to stop counting major acts of parliament, such as the restructuring of the NHS, as equal to a ruling on the ingredients of a Cornish pasty.