In an September 29, 2009 email from Michael Mann at PSU to Andrew Revkin, a New York Times environmental reporter, Mann says:
Skepticism is essential for the functioning of science. It yields an erratic path towards eventual truth. But legitimate scientific skepticism is exercised through formal scientific circles, in particular the peer review process. A necessary though not in general sufficient condition for taking a scientific criticism seriously is that it has passed through the legitimate scientific peer review process. those such as McIntyre who operate almost entirely outside of this system are not to be trusted.And yet on July 8, 2004, Phil Jones wrote to Michael Mann:
The other paper by MM is just garbage - as you knew. De Freitas again. Pielke is also losing all credibility as well by replying to the mad Finn as well - frequently as I see it. I can't see either of these papers being in the next IPCC report. Kevin and I will keep them out somehow - even if we have to redefine what the peer-review literature is !So those who operate outside the peer review process are not to be trusted--and if need be, they will change the definition of peer-review literature to keep peer reviewed papers from being included.