LONDON--An inquiry cleared British climate researchers of wrongdoing on Wednesday after their e-mails were hacked, leaked, and held up by skeptics as evidence they had exaggerated the case for manmade global warming.
Former government adviser Ronald Oxburgh, who chaired the panel, said he had found no evidence of scientific malpractice or attempts to distort the facts to support the mainstream view that manmade carbon dioxide emissions contribute to rising temperatures.
The affair stoked the global debate on climate change and put pressure on scientists and politicians to defend the case for spending trillions of dollars to cut emissions and help cope with rising temperatures.
Thousands of e-mails sent between scientists were published on the Internet just before the United Nations climate talks in Copenhagen in December.
Campaigners who doubt the scientific basis for saying global warming is manmade said the leaked messages showed that the research unit at East Anglia University had taken part in a conspiracy to distort or exaggerate the evidence.
The university, in eastern England, appointed Oxburgh to investigate the Climatic Research Unit's methods.
"We saw no evidence of any deliberate scientific malpractice," Oxburgh's inquiry concluded (PDF). "Rather, we found a small group of dedicated, if slightly disorganized, researchers.
"We found them to be objective and dispassionate and there was no hint of tailoring results to a particular agenda."
Its strongest criticism was aimed at the unit's handling of statistics. It recommended that the researchers work more closely with professional statisticians in future.
Oxburgh's was the second of three inquiries into the episode to report its findings. Police are also investigating the leak.
Last month, a British parliamentary committee cleared the unit of manipulating the evidence, but criticized its handling of requests for information made by outsiders under freedom of information laws.
The third and most comprehensive inquiry, led by former civil servant Muir Russell, is due to end in May.
Benny Peiser, director of the Global Warming Policy Foundation, a climate change skeptics' think tank, said the inquiry was "rushed and superficial."
"They want to restore the trust of the public and the credibility of the researchers and that is an honorable thing to do," he said. "But they should have done a proper job."