Let me try to answer that and make a couple of points.
First, the co-chairs of the IPCC Working Group I were Susan Solomon, who is an American, and Dahe Qin, who is Chinese and is actually the head of the China Meteorological Administration. Both of them are impeccably well-qualified scientists. You couldn't find better scientists. It was because they are so good that they were able to get all the rest of the scientists to work together.
What's interesting about the IPCC process, as Andrew Weaver said at the beginning, is that it's actually drafted by scientists and it's based on peer-reviewed literature, which is literature that's in the journals and has gone through a very rigorous process.
What happens in the plenaries—for example, in Paris—is that governments negotiate the Summary for Policymakers. The Summary for Policymakers is the short version. It's again drafted by scientists, and governments' role is to ensure that it's understandable, accessible, and balanced. Of course, different governments have different views of what defines “balance”. In the end, though, they are not allowed to write anything there that the scientists do not agree with.
In the end, what this means is that the final time the gavel comes down, all the governments present there agree that the Summary for Policymakers is an adequate, proper, and balanced assessment of the current state of knowledge.