EU referendum: Will we gain or lose rights by leaving the European Union?

They were helpfully brought together in a document called the Charter of Fundamental Rights in 2000. It lists 54 rights.

These include the right to life and freedom from torture, slavery and human cloning. There is a section on rights to privacy, protection of personal data, marriage, thought, religion, expression, assembly, education, work and property.

Read more of the big EU referendum questions here

A third section bans discrimination, of many listed kinds, and recognises the right of people with disabilities to “benefit from measures designed to ensure their independence”. The fourth section includes the right to strike, to consultation at work, protection against unjustified dismissal, and to social security benefits and health care.

The fifth includes the right of free movement and residence within the EU, the right to vote in European Parliament elections and the right to good administration. The sixth includes the right to legal remedy (including legal aid), to a fair trial, to the presumption of innocence, the right not to be tried twice for the same offence and protection against retrospective laws.

The Charter is controversial. When it was proclaimed, Keith Vaz, the minister for Europe, said it “will be no more binding than the Beano or The Sun”. It was then given legal force by the Lisbon Treaty of 2009, but the UK and Polish governments insisted on a protocol saying that it did not create new rights in the UK or Poland that could be enforced by any courts.

It is not as simple as that, or else these questions and answers would be a lot shorter. One of the arguments for leaving the EU made by Marina Wheeler QC, who happens to be married to Boris Johnson, is that the UK opt-out from the Charter is ineffective, and that the European Court of Justice – the supreme court of the EU – has started to use it in judgments affecting British interests.

In any case, Britain is already bound by most of the rights in the Charter, because they are taken from EU law or from the European Convention on Human Rights.

That is a piece of popular pedantry, but, again, it is no longer as simple as it was. The EU intends to become a signatory to the Convention in its own right. You might not think that would make any difference, because the UK is a signatory to the Convention too – and it has written the Convention rights into UK law in the form of the Human Rights Act 1998. But the EU’s own Charter of Fundamental Rights, and its intention to ratify the Convention, does mean that Convention rights could increasingly be enforced under EU law.

They sound lovely. But many Convention rights have been interpreted by the European Court of Human Rights (yes, separate from the EU) in ways that their drafters did not anticipate and on questions that look as if they should be for national parliaments to decide. The ruling on the right of prisoners to vote, for example.

You could say that is how human rights law should work: the House of Commons doesn’t like it but is forced to respect the rights of an unpopular minority.

One voter in a focus group in Leeds carried out for Lord Ashcroft on the subject of Brexit expressed it bluntly: “The ability to make our own decisions, I don’t see that as a positive. If you look at what goes on in the House of Commons, it’s disgusting. They just try to get one over on each other. We would have no appeal to the Court of Human Rights. It would mean what David Cameron says goes, and if you want to challenge that, tough shit.”

You should be a lawyer. That is correct. That ruling has simply been ignored by the British Government, because the European Court of Human Rights has no power of enforcement. But the more the EU and EU law are tied in to the Convention, the more its rights – as interpreted by various courts – will be imposed by the European Court of Justice, which does have the power to enforce its rulings on the UK.

If we could paraphrase her 25 April speech, she thinks it would be easier to deport foreign criminals if we repudiated the Convention and repealed the Human Rights Act. She wants to re-inscribe Convention rights in a British Bill of Rights in a way that would limit the scope for the UK courts to interpret them in ways that get in the way of what she sees as her job as Home Secretary.

Ideally, she would like to leave the EU as well, but the economic argument and the likelihood that Scotland would break up the UK have persuaded her that we should, on balance, stay in the EU and out of the ECHR.

Yet again, not so simple. If Britain left the EU, and repudiated the European Convention, and scrapped the Human Rights Act, even then some Convention rights would remain. The laws devolving power to Scotland, Wales and Northern Ireland require the devolved authorities to respect Convention rights, so those laws would have to be rewritten. If the Scottish Parliament or Welsh or Northern Ireland Assemblies want to keep them, things would start to become awkward.

What is more, as Ms May has noted, Scotland might vote in a new referendum to leave the UK altogether and rejoin the EU and readopt the Convention.

That is one of the arguments made by the Leader of the Opposition, yes. EU law – never mind the Charter of Fundamental Rights – gives rights to workers, consumers, women and others that they wouldn’t necessarily have from the UK government.

On the other hand, you could imagine that, if we had a Labour government, Mr Corbyn might not be so keen on the EU protecting the rights of, say, businesses and employers.

EU law can also create rights that we don't expect. When the Labour Party's all-women shortlists were ruled unlawful in 1995, that was under the EU Equal Treatment Directive. The ruling was later changed by an exemption for political parties in UK legislation by the Labour government.

It all depends at which level you think these decisions should be made.

The big argument of the Leave side is that we would regain full national sovereignty, which means our right as a country to make our own laws and to decide who can come into the country and who cannot. But that is a huge question in itself, and will be the subject of another Q&A in the next few weeks.