Once in a while, in these days of antagonism towards the political-legal establishment, something happens that gladdens the heart. The ruling yesterday by three of the UK’s most senior judges in the long-running defamation case against the science writer Simon Singh was one such moment.

The Lord Chief Justice, Lord Judge, and his appeals panel have not just ruled against a critical aspect in the case brought by the British Chiropractic Association (BCA). They have set a precedent that should make it considerably harder for organisations to try it on in this way in the future.

For Index on Censorship and our partner organisations, this marks the latest victory in our campaign to reform England’s hideous libel laws. Since we launched our 10 proposals for change last November, we have seen public opinion shift steadily in our favour, with the law struggling to keep up.

Singh’s two-year campaign has already cost him £200,000 in fees. It is testament to his courage that he has seen it through. Time and again in recent years other scientists, authors, journalists and NGOs have decided to settle, and to apologise, simply for fear of destitution. Too often they have had nothing to apologise for, but have been bullied into it.

In his ruling, Lord Judge condemns the use of protracted litigation for its “chilling effect on public debate”. The judgment made clear that Singh’s negative remarks on chiropractic care were “honest opinion”, rather than a statement of fact, thus sparing him the need to prove his case through evidence – and delivering a telling rebuff to the libel-judge-in-chief, Justice Eady, who had ruled against Singh last May.

“[Singh’s] opinion may be mistaken,” the panel said, “but to allow the party which has been denounced on the basis of it to compel its author to prove in court what he has asserted by way of argument is to invite the court to become an Orwellian Ministry of Truth”.

The courts must still adjudicate on the claim for defamation, but on the strength of this verdict, the BCA will be under considerable pressure to withdraw its claim.

John Kampfner is Chief Executive of Index on Censorship