Tomorrow could mark a significant day for British newspapers.

Or, in the words of today’s Sun editorial: “Tomorrow the government faces a decision that could destroy our free press and fundamentally undermine the principle of natural justice in Britain.”

What is going on?

Around four years ago, after conducting a High Court inquiry into the ethics of the journalism industry, Lord Justice Leveson made recommendations on how press regulation in the UK should be run.

The government subsequently enacted a royal charter on press regulation, which created the Press Recognition Panel (PRP). The quango was set up in order to recognise a press regulator meeting the requirements set out by Leveson.

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The press, outraged by any government involvement in regulation, went off and set up their own regulator, the Independent Press Standards Organisation (Ipso).

Ipso, which was founded in September 2014, has been signed up to by the majority of newspapers – national and regional – in the UK, as well as other magazines and websites.

Ipso has not, and does not plan to, apply for recognition under the PRP because its members view the Leveson requirements as a step towards state regulation of the press.

Meanwhile, a rival regulator called Impress, which counts a small number of titles such as the Caerphilly Observer, Positive News and Byline as members, has applied to the PRP for recognition.

The PRP will meet tomorrow to discuss Impress, and is expected to recognise the challenger regulator.

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What’s the problem?

If the PRP approves Impress’s application, the government then has the option to invoke Section 40 of the Crime and Courts Act 2013.

If Theresa May’s government does this, newspapers and other publications which are not members of Impress are in trouble.

This will mean when newspapers are sued for libel, they face paying the claimants’ legal fees – regardless of whether they win the case or not. In essence, it becomes free to try and sue a publisher. They will also face exemplary damages.

What the newspapers are saying

Daily Mail:

This would hand a blank cheque to anyone to sue any newspaper, however risible their case, knowing it won't cost them a penny. For many local newspapers, already under immense financial pressure, having to face such court actions will be the final straw. Put simply, this is blackmail: sign up to the phoney state-endorsed regulator or face obliteration in the courts.

The Sun:

Signing up to Impress would mean granting the state an indirect hand in what the once-free press could publish, when it is the primary job of the press to hold those in power to account. Today, the Sun appeals directly to Theresa May: Do not let this historic calamity happen on your watch.

The Sunday Times:

Section 40 would achieve what newspapers warned of when the royal charter was proposed: the first state regulation of the press for more than 300 years. The prime minister can prevent this by refusing to agree to implement section 40. She must do so.

Matthew Parris in the Times:

Imagine your angry next-door neighbour thinks a tree in your garden spoils his view. He wants to sue, but isn’t confident he could win. Now he learns that there’s been a change in the law. He can sue you, and even if he loses, you will have to pay his legal costs — unless the judge decides this would not be “just and equitable in all the circumstances”. Alice in Wonderland? Evidently. But that is what Section 40 would do to newspapers. It would allow anyone to take libel action against a local or national newspaper knowing that the defendant — the journal — will probably have to pay the costs even if they win the case. It’s like sticking a “kick me” sign on somebody’s back. This is so cockeyed as to defy satire.

The opposing view

Amber Melville-Brown, Withers LLP: