This article by Raymond Lehmann (Bestwire) points out a number of interesting things about why med mal pricing is hard to understand. Lehman asks the big questions to a number of people and gets slightly different answers. (I noted this confusion before, but I wasn't really sure of the bottom line.) Med mal is not experienced rated because a single claim (or even a group of claims) against a physician does not truly mean the doctor is more risky than another doctor. Judge Posner's blog even gets a mention as he asserted correctly (and received a bunch of flack) that med mal writers do not really engage in experience rating of physicians in the way that most people would understand experience rating.