Sir Aaron Klug is right (page 15) that there are too few disinterested experts to supply the many scientific advisory committees. The scarcity is acute in biotechnology and information science but arises everywhere from food safety to railway signalling.
A key role of universities is to shelter critics whose advice may be uncomfortable or unfashionable. Another is as a principal source of innovation. Critics are often associated with pressure groups; inventors with consultancy fees, share options and directorships. Both views need to inform policy and both groups have vested interests.
The first thing people who assemble committees need to know is who is incapable of working with people of opposing views. Next they (and those who recruit reviewers for journals and grant applications) need a full declaration of an individual's interests. Conflicting interests can then be balanced.
Such declarations must be complete. A grant from a research council may not seem compromising but the spin-off may set up an interest. Research for a government department may be subject to pressure. Grant-awarding charities use findings for lobbying purposes. Nor do people have to receive money to have a vested interest. Anyone in the Cambridge Computer Laboratory, for example, has one whenever Microsoft, a major laboratory supporter, is mentioned.
Declarations also need to be straightforward. There is a lesson on what to avoid in the cumbersome forms the civil service send people applying to be on public bodies.
Establishing such guidelines is infinitely preferable to excluding anyone with contacts in the outside world from an advisory role.