I've not blogged about the Stern Review analyzing the impacts of climate change because I've not had anything intelligent to say. But I haven't let that stop me in previous situations, so here's a far-fetched analogy.
I found really interesting the number of people, especially my fellow lawyers, who were outraged by the Supreme Court decision to hand the 2000 election to Bush, but never actually read the decision. Here it is. When I read the "per curiam" decision of the five judges, I found that it really analyzed four or five separate questions that led to their ultimate conclusion. For each one of those questions, my thinking was something like "well, I disagree with that particular argument, but I can see that someone might reach that viewpoint." The problem was that every single one of those subsidiary questions had to be answered in the way the majority did for them to be able to get the conclusion they wanted - Bush as president, and no recount for Gore. That combination of always picking the subsidiary outcome in the direction they wanted it to go was what convinced me of bias.
So that leaves the Stern Review. RealClimate has a rundown of the science issues, and my superficial impression of the economic issues is similar: "he strays on the high side of various estimates and picks the high side to talk about in the summary. This high-end bias lends the Review open to charges of 'alarmism'."
I don't think this requires conscious bias, however. I'd guess that at least two of the Supreme Court conservatives (O'Connor and Kennedy) weren't consciously choosing to throw the election to their guy. And unlike the Supreme Court case, I think many of the choices Stern makes are defensible. The problem that they always seem alarmist is what's disturbing.
I think this is too much and too important for a single person and project. It really should be made a regular part of the IPCC process. And rather than giving a single outcome for things that require value judgments, like social time discounting, they could split the analysis and give alternative outcomes depending on which value judgment you choose.