It's the following two notes, included on the list of participants (
https://www.gov.uk/government/publi...f-participants-of-sage-and-related-sub-groups) which I think creates some distrust of the claims that the advice is objective and purely based on the available science...
Not for me, I have been part of, and led teams advising Government (not at the level of SAGE I hasten to add) and we would often have observers, who could even ask questions, but this had no effect on the advice we eventually gave. It is after all just advice, the government listens to the advice, puts it into the wider context of running the country, and applies it as they see fit.
Although no one can be 100% objective, scientists take a lot of pride in their science and their endeavours to be objective, so while this is no guarantee of anything, I'm not overly concerned about the objectivity of the advice or of it not being based on the available science.
However, the problem is that in any situation, the available science is still open to professional interpretation. There is rarely consensus amongst scientists because science, by its very nature, is full of uncertainty. And as the evidence changes, the individual beliefs of individual scientists will also change, but not necessarily in the same direction. They may well have come up with a strategy that brokered the least amount of disagreement, but it would also highlight the risks of that strategy along with the risks and benefits of alternative strategies. (at least that is what we used to do)
Different scientists will bring different views to the table, and it might well be that the Government has chosen to take advantage of the unavoidable uncertainties and follow the scientific opinions that best fit with other Government policies.
But that apart, I am more concerned about what the Government might mean when they say they are following the best scientific advice. A cynical view might go something like this:
Scientists: The best possible strategy, is strategy A
Government: We don't like strategy A, have you looked at our proposed strategy B
Scientists: Strategy B would be a disaster
Government: OK, What about our proposed strategy C
Scientists: Well, it would be a bit better than strategy B.
Government (to public): Following best scientific advice, we have abandoned strategy B and are following strategy C (strategy A meanwhile remains confidential)
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