Warwick Hughes, an Australian scientist, wondered where that "+/-" came from, so he politely wrote Phil Jones in early 2005, asking for the original data. Jones's response to a fellow scientist attempting to replicate his work was, "We have 25 years or so invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it?" [...]
Then the story changed. In June 2009, Georgia Tech's Peter Webster told Canadian researcher Stephen McIntyre that he had requested raw data, and Jones freely gave it to him. So McIntyre promptly filed a Freedom of Information Act request for the same data. Despite having been invited by the National Academy of Sciences to present his analyses of millennial temperatures, McIntyre was told that he couldn't have the data because he wasn't an "academic." So his colleague Ross McKitrick, an economist at the University of Guelph, asked for the data. He was turned down, too.
Faced with a growing number of such requests, Jones refused them all, saying that there were "confidentiality" agreements regarding the data between CRU and nations that supplied the data. McIntyre's blog readers then requested those agreements, country by country, but only a handful turned out to exist, mainly from Third World countries and written in very vague language. [...]
Enter the dog that ate global warming.
Roger Pielke Jr., an esteemed professor of environmental studies at the University of Colorado, then requested the raw data from Jones. Jones responded:
"Since the 1980s, we have merged the data we have received into existing series or begun new ones, so it is impossible to say if all stations within a particular country or if all of an individual record should be freely available. Data storage availability in the 1980s meant that we were not able to keep the multiple sources for some sites, only the station series after adjustment for homogeneity issues. We, therefore, do not hold the original raw data but only the value-added (i.e., quality controlled and homogenized) data."