I have always been bothered by that old joke - Question: What do you call the person who graduated last in his medical school class? Answer: Doctor. I think about this joke when I am approached by lawyers asking whether I will be an expert witness. Maybe, I hope, there is some good I can do. Maybe; but experience has also taught me: maybe not. Shakespeare had a character once famously say: "First, let's kill all the lawyers." He exaggerated, but he also had an insight.
I have worked on a few legal cases (about half a dozen over a decade). I don't make a living at it (those who do receive the esteemed "hired gun" moniker), and I don't really enjoy it. I had never even really thought deeply about why I did it. My father, long ago, had admonished me to avoid testifying against my fellow physicians; it smacked of hubris, he implied, and I was no better than the worst of them. But that medical school joke still bothered me.
I know that doctors can cause harm. The Institute of Medicine estimates that at least 50,000 patients are killed yearly by medical error. And these are chance mistakes: leaving the IV in the arm too long, not wiping with alcohol before insertion, not cleaning one's hands thoroughly, mistaken dosing on a prescription. How many more deaths, I wonder, happen with systematic error, with our own blindnesses and dogmatisms? Suppose I do not believe there is such a thing as bipolar disorder; or if it exists, I might be believe it's way overblown; so I will rarely, if ever, diagnose it. If I think that way, then persons with bipolar disorder, to whom I gave the wrong treatments, do not get well, even though lithium (for instance) might have cured them.
I always wondered about how my own research, demonstrating that we psychiatrists frequently misdiagnose illnesses and that we give incorrect treatments, argued against a facile acceptance of the "standard of care."
Thus, when lawyers came to me, based on my published research, to ask my views either for or against a plaintiff or a doctor, I thought it was my responsibility to provide my knowledge, and to take what I think is correct as a matter of science and teaching, and state what it should mean as a matter of medical practice. I only took those cases in which I felt my expertise was important and where something clearly wrong had occurred. I suppose I felt a bit comfortable in the truth.
Recently, though I found myself face to face with a sneering lawyer who informed me that one of my mentors was the expert witness for the opposite side. Given that my teacher had taught me much of what I know, I wondered how it could be, in a legal setting, that two experts who share almost all the same views could end up testifying to opposite conclusions. The lawyer who hired me told me he sees this scenario all the time; even co-authors of major textbooks end up testifying to opposite judgments.