I think Sheila Jasanoff’s work addresses some of the salient issues here. One possible reform she discusses in Science at the Bar: Law, Science and Technology in America (1995) is ‘the idea of strengthening the technical supports available to judges. Frequently discussed options include the increased use of court-appointed experts, special masters or technically trained law clerks in complex cases.’ Furthermore, she cites the Federal Rules of Evidence, ‘which grant judges broad powers to seek help from court-appointed experts or panels if they believe that such procedures will assist the process of scientific fact-finding. The power, in practice, is only rarely used by the federal courts.’ However, in addition to some practical problems with such proposals (in itself not an insuperable obstacle), ‘support for the greater use of court-appointed experts rests on the largely unexamined assumption that the removal of fact-making from the exclusive control of the disputing parties will produce and unbiased account of scientific information.’ More workable strategies include ‘educating judges, lawyers, and scientific experts in each other’s modes of reasoning and discourse.’ Finally, she suggests ‘lowering the stakes for both winners and losers…might serve justice while reducing the the temptation for purely opportunistic uses of science.’ Of course none of these, singly or in concert, are definitive solutions, but they might help us come up with creative ways to counter insidious and ubiquitous commodification processes associated with expertise. (I can’t help but recall one reason Socrates criticized the sophists!)

Perhaps also worth a look is Douglas Walton’s work on arguments from authority, for instance, his Appeal to Expert Opinion: Arguments from Authority (1997) and several related papers available here: http://io.uwinnipeg.ca/~walton/p_and_p.htm

as well as his Legal Argumentation and Evidence (2002), in particular his discussion of the ‘peirastic dialogue’ as ‘a type of verbal exchange between two parties, one of whom is an expert in a skill or domain of knowledge, and the other of whom is a layperson (nonexpert) in that field.’

Walton addresses the following dilemma, after Sextus Empiricus (attributed to Anarchasis of Scythia and here according to Walton):

Who is to be the judge of skill, the expert or the nonexpert?

It cannot be the nonexpert, for he lacks the skill.

It cannot be the expert, for his skill makes him a biased judge.

Therefore, nobody can be the judge of skills.

Expert who are basically willing to testify to anything if you pay them enough have a limited lifespan. After a number of lawsuits, the glaring inconsistencies and blatant distortions start to become more apparent, and they’re discarded for someone with a less sullied record.

On the other hand, I remember a story about Professor Scherer was testifying on behalf of the FTC to block a merger through a preliminary injunction. The defense attorney asked him on cross, “How much are you being compensated for your testimony today?” “Nothing.” Scherer replied.

The astonished defense attorney couldn’t help himself and asked “Why is that?” “I just felt so strongly about this being an anticompetitive merger, that I agreed to provide my services to the government free of charge.”