'To greens, I was worse than a child abuser'

Martin Durkin's documentary 'The Great Global Warming Swindle', aired on Channel 4 last year, enraged the green lobby by claiming human activity wasn't behind global warming. Ofcom, the TV regulator, received 265 complaints and last month ruled that its writer and director lacked impartiality. However, Ofcom ceded that, despite "certain reservations", it did not believe audiences had been "materially misled". Writing for the first time since the documentary was screened, Durkin tells 'The Independent on Sunday' why he stands by his film in the face of continued criticism.

The fuss over Swindle is a bit like Fatal Attraction: every time I think it's over, up pops Glenn Close, looking rather like George Monbiot of The Guardian in a wig, and takes another swipe at me with a kitchen knife.

The latest dramatic episode is Ofcom's adjudication on the many complaints about the film.

Swindle went out more than a year ago and ordinary viewers loved it: the duty log was swamped with calls, 6:1 in support. Evidently many of them thought this global warming stuff was baloney, and were rather relieved that someone had stood up and said as much.

The BBC's environmental journalists were embarrassed. Why hadn't Roger Harrabin and his crew raised any of the issues I had covered in Swindle? Take the famous Ice Core data. This was the jewel in the crown of global warming theory. Al Gore said it proved a link between carbon dioxide and temperature. He failed to mention that in the data the connection was clearly the wrong way round – temperature driving CO2 levels, not the other way round.

Harrabin had to go on to Newsnight and put some of these obvious points to Gore in person. Big Al squirmed and evaded and, according to Harrabin, later accused him of being a "traitor"'.

As it happens, I have made a number of science documentaries debunking irrational scare stories, and the greens have had a whack at me before – scares are the oxygen of the green movement. And I know from experience how illiberal these liberals are. But even I have been stunned by the sustained ferocity of their response to Swindle.

Besides a vitriolic campaign in the press, the instrument of their fury has been Ofcom. A swift internet campaign rallied the troops. Hundreds of complaints were sent off, many using the same phrases and displaying a surprisingly good knowledge of the Ofcom code.

Every line in the film was subjected to scorn. The contributors were all in the pay of baby-strangling capitalists. As for me? I was a member of the special steering committee of the World Congress of Science Producers. I had recently won an award from the British Medical Association for making the best science documentary of the year. But now I was "worse than a child abuser".

One complaint stood out. It ran to 200 pages and was orchestrated by three "concerned citizens". It claimed to be peer-reviewed, which it wasn't. But it was backed by the great and good of the global warming brigade.

Our response was long and detailed: 300 pages, not counting supporting science papers etc. What has been the result?

To heighten the dramatic effect, let's compare Gore's beloved Inconvenient Truth with Swindle. The veracity of Al's film was tested in the High Court, when a lorry driver from Kent baulked at the prospect of his taxes being spent on disseminating it to British schools.

The verdict was a blow to the greens. Mr Justice Burton cited at least nine significant "errors" in Gore's film. Using words such as "alarmism" and "exaggeration", the judge said the film couldn't be sent out to schools without a health warning.

Harrabin wrote a piece admitting he had thought the film was a bit off when he first saw it. Did he indeed? So why didn't he tell the rest of us? What do we pay him for? And how about all those "scientists" who, to their eternal shame, lined up to heap praise on the film?

Now let's look at Swindle. The global warmers made buckets of complaints to Ofcom that the science was wrong, that the film contained hundreds of factual errors, falsifications and misrepresentations. It was, in short, unscientific and scurrilous.

How many of these complaints did Ofcom uphold? Not one.

So what did the regulator say? Well apparently we could have been a bit clearer with an oceanographer we interviewed about what the final film would look like. We gave the Intergovernmental Panel on Climate Change (IPCC) nine working days to respond to our allegations; apparently we should have given it 10. And we didn't give a right to reply to the UK's chief scientific adviser, David King, who did not appear in the film but whose entertaining views on global warming were alluded to. These were such insignificant infringements of its code that Ofcom has not asked Channel 4 to apologise to anyone.

How was all this reported? In Australia, The Herald Sun ran the headline, "Great Global Warming Swindle Cleared". Its columnist, Andrew Bolt, wrote: "This witch-hunt against The Great Global Warming Swindle has failed utterly to discredit it, discrediting instead the accusers." The Sydney Morning Herald declared, "Lonely Voice of Dissent Declared Valid", adding: "There is something odd about the ferocious amount of energy expended suppressing any dissent from orthodoxy on climate change. If their case is so good, why try so fervently to extinguish other points of view?"

Over here, it was a different story. The greens were furious Ofcom hadn't played ball, but tried their best to spin the decision. According to Newsnight, Channel 4 had had "its fingers burnt". Suddenly the report was said to be "damning".

The most surreal response came from the head of the IPCC: "We are pleased to note Ofcom has vindicated the IPCC's claim against Channel 4 in spirit and in substance."

Meanwhile, in the "liberal" press, the attacks continue. Some bloke called Leo Hickman said the film was "toxic" and George Monbiot emerged from his bath- tub again slashing and slashing. The film, he reminded us, was a "cruel deception" and, he asked innocently: "Why is Channel 4 waging war against the greens?"

Sadly I missed all this. I was taking my family round the US in a gas-guzzling Winnebago. My reading matter was Milton Friedman, who writes: "It is entirely appropriate people should bear a cost – if only of unpopularity and criticism – for speaking freely. However, the cost should be reasonable and not disproportionate. There should not be, in the words of a famous Supreme Court decision, 'a chilling effect' on free speech."

In the year that has passed since the film was broadcast, I have discovered what that "chilling effect" is. It is when a programme maker needs to risk his career in order to make a particular film. It is when a commissioning editor or a broadcaster is genuinely fearful of straying into certain areas.

The main Ofcom complainant noted: "This is Not an Attack on Free Speech". So rather than try to shut me up, bully and vilify, why don't they engage in an honest discussion about the science?

I'll tell you why. Because the theory of global warming is crumbling round their ears. For the past decade now, world temperatures have been static or slightly declining – and that's according to the IPCC. I don't remember their silly models predicting that 10 years ago.

I no longer give a stuff whether left-liberal types agree with my views on global warming. However, I do expect every last one of them who claims to value the freedom to speak one's mind, to defend my right to air them.