In a memo Tuesday, the NSF's Inspector General's office said that "the research in question was originally completed over 10 years ago. Although the subject's data is still available and still the focus of significant critical examination, no direct evidence has been presented that indicates the subject fabricated the raw data he used for his research or falsified his results."
"Lacking any direct evidence of research misconduct," the review concludes, "as defined under the NSF Research Misconduct Regulation, we are closing this investigation with no further action."
The investigation centered around thousands of e-mails stolen from the University of East Anglia's Climate Research Unit in Great Britain, that showed scientists discussing how to keep research skeptical of climate change out of peer-review journals, among other things. Conservatives and climate skeptics latched onto the e-mails, using them as evidence that the idea of man-made climate change is not true. The e-mails did not, in fact, undermine the broad consensus that climate change is occurring.
Mann himself was accused of committing fraud when obtaining government funds for research into human-caused climate change while he was at the University of Virginia, and then manipulating the data.
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