In 2008, I published a piece here in the Guardian pointing out that the British Chiropractic Association (BCA) was promoting treatments that were not backed by any worthwhile evidence. Instead of debating the evidence, the BCA sued me for libel.

At that same time, Ben Goldacre was being sued by Matthias Rath because of articles also published in the Guardian, which criticised Rath's promotion of vitamins to treat HIV in Africa. These two cases and many others in the last few years have demonstrated how our libel law was being used to chill debate on matters of serious public interest. As a result, doctors, academic journals, Mumsnet, investigative journalists, bloggers, Which?, human rights campaigners and others joined together to form a grassroots campaign to reform libel law so that the rich and powerful could no longer silence their critics.

Meanwhile, in parliament the biggest early day motion of the session, a select committee report and a Ministry of Justice working group showed there was cross-party support for libel reform, and last year Nick Clegg promised to turn "English libel laws from an international laughing stock to an international blueprint".

Finally, a defamation bill was announced as part of this week's Queen's speech and it is expected that the bill will be published shortly. The justice minister Lord McNally has already published a draft bill, so we can get a sense of what it will contain. There are several clauses that will receive universal support, such as barriers to libel tourism and increased protection for academic discussion.

However, there are four important areas of concern, which need to be addressed to make sure that the final bill delivers a truly fair libel law. First, we need to make sure that trivial or vexatious libel claims are no longer possible. Too many groundless claims run up massive bills before they are eventually thrown out or lost. Second, the defamation bill needs to take into account the new issues that arise due to the internet. For example, it is too easy to censor an important blog by threatening the online host. The host, who probably charges between zero and £10 per month, then pulls the blog because it is unlikely to risk £100,000 defending a citizen journalist. Third, the draft public interest defence is still inadequate and will not sufficiently protect those who work on our behalf to expose wrongdoing. The draft bill merely describes a modified version of the current so-called Reynold's defence, which is known to be unreliable, expensive and confusing. Fourth, there is no clause that restricts the ability of corporations to sue for libel.

The concern arises because many of the libel cases that triggered the reform campaign were brought by corporations. These corporations have a major influence on society and should be held to account, but at the same time journalists can be intimidated by the huge financial resources that corporations can put into a legal action. In my case, I estimate that the members of the British Chiropractic Association have an annual turnover of £100m, and the BCA decided to sue me personally. I was very close to backing down and apologising for an article that was fair and accurate. For similar reasons, you can imagine how a local newspaper, a blogger or an NGO would refrain from criticising corporations on issues that the public ought to know about.

Libel law was developed to protect the reputations of individuals, not corporations. The Libel Reform Campaign proposes that corporations should be able to bring a libel action only if they can show actual financial harm and malice or reckless disregard for the truth. Beyond libel law, it is important to remember that companies could respond by using their PR teams to rebut criticism, obtaining declarations of falsity, and use the law of malicious falsehood and business protection regulations.

These avenues for redress may not be sufficient for small companies, such as the corner shop who has been defamed, but the owner still has the right to take out a personal libel action. In short, the Libel Reform Campaign's proposals are appropriate for all companies, large or small.

This sort of approach, which puts the rights of the public ahead of large corporations, has been effective in Australia and America. Last year, I attended a meeting of roughly 30 interested parties, including lawyers and legal academics, and there was unanimous support for the restriction of corporations to sue for libel.

Unless someone from the Ministry of Justice is willing to put forward the other side of the argument and explain why something more akin to the American and Australian attitude to corporation is not acceptable in the UK, then I expect that one of the first amendments to the bill will protect honest journalists from being intimidated.

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