As does "honest", immune from influence, and free of vested interests.
A bit like truly impartial (and unprejudiced - in the true meaning of the word) juries these days ... often hard to find.
Even an independent engineer still has "form" (a history, how he arrived where he is today, and all the rest).
"Certified" (P.E., and all the rest) really just means that the guy can afford an annual subscription somewhere, and also the possibility (somewhat remote, in actual fact) of censure if he screws up
too badly along the way. Just look at how many doctors of medicine still continue to practise (and yes, practice
does make perfect ... given enough time) even after a string of the most gravest of er,
errors. And how can an "expert witness" ever expect to convince people that he is working in "splendid isolation" (that is, without influence from others, even if it is only in the academic sense - and it would be that, at least). Who can agree that the guy is an "expert", apart from his peers (in other words, other experts)? If (heaven forbid) I were ever to be challenged by an expert ... the first thing I (and most others, I should imagine) would do is challenge the expert's expert status!
In short, I disagree with the notion of bringing in a specialist. Far better, I would have thought, to bring in a generalist, with an ounce or two of Common Sense. I would argue that only if the guy had no detailed prior knowledge of the kit concerned could we hope for a truly unbiased, but honest and frank opinion.
The Defence now rests.
Meanwhile, my earlier advice still stands. That is, keep well away from it if at all possible. Historically, the medics always win, whilst the biomeds er,
lose. The medics not only hold all the cards, but also have the Big Guns. Meanwhile, we (being the lowest of the low) have, er ... nothing.