I spent Tuesday night at the Barley Mow pub in Westminster, central London, surrounded by 150 people who were outraged at the state of English libel laws. The event, which is part of a series of Skeptics in the Pub events around the country, started with a misquote from Star Wars that set the tone of optimism for the entire evening: “We are more possible than you can powerfully imagine.”

The mob, clamouring for a more liberal approach to free speech, was made up largely of bloggers, academics and sceptics. They all passionately share the same belief, which is that the freedom to criticise fairly and strongly is the cornerstone of debate and progress.

One of the main fears, expressed repeatedly during the evening, was the sheer cost of a libel case. Although the damages at stake might be just £10,000, going to trial can mean risking more than £1m. This means that a blogger has to ask whether he or she can afford the possibility of bankruptcy. Even if a blogger is 90% confident of victory, there is still a 10% chance of failure, which is why bloggers often back down, withdraw and apologise for material they believe is true, fair and important to the public.

I should point out that I am being sued for libel by the British Chiropractic Association. Indeed, last week I was at the Court of Appeal where I received permission to appeal against an earlier ruling on the meaning of my article. The original article was published 18 months ago, the case has cost me £100,000 and there is still a long way to go. My reason for not backing down is that I believe my article is accurate, important and a matter of public interest, as it relates to the use of chiropractic in treating various childhood conditions, such as asthma and ear infections.

Although my article was published in The Guardian, I am being sued personally. Fortunately, thanks to the success of my books, Fermat’s Last Theorem and The Code Book, I have the resources to fund my own defence. The case might seriously damage me but it will not bankrupt me. For bloggers, such a case could lead to financial ruin.

Allen Green, the event organiser, who blogs as Jack of Kent, summarised sentiment thus: “There is uncertainty and trepidation. The law currently treats bloggers as publishers, so they carry all the same legal risks of a publisher.”

For example, the website Bad Psychics has been forced to remove an article about a psychic healer. This problem was reported by Andy Lewis, who runs the Quackometer website and who is one of the most tenacious and insightful bloggers on the web. However, even Lewis fears the intimidation brought about by English libel law: “In light of what happened to Bad Psychics, I have to think seriously about what I write.”

Even if a blogger is prepared to stand by a blog, he or she can be undermined by the company hosting the blog. When the Society of Homeopaths took offence at Lewis’s criticisms of its regulatory practices, it threatened his web-hosting company. The company had no reason to put its neck on the line for a blogger who was paying just £9.99 a month, so it took down his blog. Luckily, Lewis’s blog has found virtual shelter with the Positive Internet Company, which is run by a team that cares about free speech on the web. It welcomed him with a brief e-mail: “I note your cowardly hosting company censored your homeopathy post. I am happy to offer you free hosting at my company. I hope you’ll find we’re sturdy vertebrates!”

The academic David Colquhoun, professor of pharmacology at University College London, was another blogger who dared to criticise a therapy that he felt lacked clinical support. After writing about the herbal medicine red clover, his university received a letter threatening legal action because it was hosting Colquhoun’s supposed defamatory blog. UCL removed the site after taking legal advice. Although the university later decided to welcome the professor back, partly due to pressure from academics around the world, he has also moved his blog across to Positive. It is important to note that academic journals also receive libel threats. Colquhoun himself was threatened for an article about chiropractors published in The New Zealand Medical Journal last year. Fortunately the editor was not prepared to back down, responding: “Let’s hear your evidence, not your legal muscle.”

Even academics being interviewed have to fear libel. The cardiologist Peter Wilmshurst gave an interview to an American journalist about a new device that he was testing. The company behind the device is now suing him. If he loses the case, he may also lose his house.

Few cases get to trial, but the bigger problem is that bloggers and academics are regularly censoring their own material in order to avoid litigation, and often they avoid writing about certain topics, companies and people.

Exactly the same situation exists in national newspapers. Events last week may have shifted public feeling towards a realisation that our libel laws are unjust and we are no longer a land of free speech.

There are clear ways forward, such as drastically reducing libel costs by capping fees, and introducing a public interest defence to protect those writing about health, safety and other issues. However, there has to be public support to push this issue up the political agenda.

Keep Libel Laws Out of Science has started a campaign for libel reform, which will have an effect far beyond the world of science if it is successful.

A statement already has 20,000 signatories, including the astronomer royal, the poet laureate, Richard Dawkins, Stephen Fry, Ricky Gervais and Dara O’Briain. To add your name, visit www.senseaboutscience.org/freedebate.

The problem of libel is partly about what we as journalists, bloggers and academics can write, but it is also crucially about what you are allowed to read.

You deserve the same access to information as the rest of Europe and America.

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