I often tell my students that they must not believe a single word of what I say, and that they must check the facts for themselves. I am afraid most of them will only follow my first advice; they are not willing to believe me but don’t bother to check the facts either. Worse than this, other students may follow none of my advices, and the fact that I offer such honest advices may make them more, not less, gullible.
Roger Pielke often writes about the role of scientists as policy advisers, for example on matters of climate change. He contrasts “the honest broker who works to expand (or at least clarify) the scope of choice available to decision makers,” with “the issue advocate who works to reduce the scope of choice.” Pielke envisages these two types as extremes along a continuum.
I doubt that truly honest brokers can exist. A scientist, or anyone, who is able to offer (seemingly) balanced arguments for and against several conflicting ideas may thereby gain the trust of his audience. He may, unconsciously or strategically, exploit that earned trust to promote his own agenda in subtle ways. By being subtle and (seemingly) trustworthy he may be more effective than the issue advocate. Issue advocates are likely to breed scepticism among educated listeners; (seemingly) honest brokers breed trust.
In case truly honest brokers existed, I would not be able to tell them apart from wily brokers. At most, I could try to check the facts for myself (a daunting task) or find another wily broker carrying a subtly different message. In other words, when faced to a policy dilemma I can try to make up my mind by listening to two opposed issue advocates or to two opposed (seemingly) honest brokers. I am not sure what I prefer.