Is the term "Peer Reviewed" important and of any use when evaluating AGW literature?

We know from the emails of Phil Jones, Michael Mann, and others at the IPCC that there were unscrupulous dealings between those writing the emails, and one of the most egregious was the use of their positions as editors of certain publications, their positions being granted because of their positions with the IPCC, to stop the publication of studies which would tend to undermine their stance on Anthropogenic Global Warming. Is it proper to deny publication simply because one disagrees with the position of the research report? Has this particular branch of science, become too highly politicized to be trusted?