for a firm that handled med-mal cases while in law school. Basically a doctor has to cause permanent damage, beyond scarring, as a result of gross error for a plaintiff to have a chance.
If a doctor leaves a sponge or instrument inside you and it causes no permanent damage to an organ......likely no case because they can cut on the original incision to remove so that there is no additional scarring.
I agree that there are some oily attorneys out there, but it's pretty rare in the med-mal area because the cases are extremely expensive and all done on a contingency fee basis. It'll cost an attorney well into 6 figures to secure all the relevant experts and to try the case, so to just get back his investment (as part of the 30% retainer) the award has to be significant.
I agree that there is defensive medicine....no doubt. BUT, if you exclude all the defensive medicine/threat of litigation, there is still a significant monetary incentive for doctors to order more tests.