I have tried several times, with varying degrees of success, to tackle the “consensus ain’t science” shibboleth. (See especially here and the comments here).

Andrew Dessler recently took an excellent stab at this in a couple of posts: see here and here.

Might a “consensus” position be wrong? Of course. All knowledge is provisional and subject to future revision as new data comes in. However, as policymakers, the scientific consensus is the position most likely to be correct. In particular, strongly held consensus positions (e.g., smoking causes cancer, the Earth is warming) are verly unlikely to turn out to be wrong. Policymakers can do no better than to follow the scientific consensus in formulating their policy.