Suppose a group of scientists introduced a new cancer drug that they claimed could save many lives. There were side effects, of course, but they claimed that the benefit far out weighed these risks. The government than asked these scientist to form an assessment Committee to evaluate this claim. Colleagues of the group of scientists who introduced the drug are then asked to serve on this Committee, along with the developers.

If this occurred, of course, there would be an uproar of protest! This is a clear conflict of interest.

Yet this is what has happened with the IPCC process! The same individuals who are doing primary research in the role of humans on the climate system are then permitted to lead the assessment! There should be an outcry on this obvious conflict of interest, but to date either few recognize this conflict, or see that since the recommendations of the IPCC fit their policy and political agenda, they chose to ignore this conflict. In either case, scientific rigor has been sacrificed and poor policy and political decisions will inevitably follow.
http://climatesci.colorado.edu/2007/09/01/the-2007-ipcc-assessment-process-its-obvious-conflict-of-interest/