Democrats and some Republicans in the Michigan legislature are lending support to a trial-lawyer-backed push to eliminate an Engler-era product liability provision unusually favorable toward pharmaceutical companies. (The existing law shields drugmakers from being sued over FDA-approved actions unless they've misrepresented facts to the agency; although trial lawyers do typically claim after drug recalls that drugmakers engaged in such misrepresentations, they don't look kindly on a law which puts them to the proof of such allegations). The bill being filed by Democratic lawmakers would eliminate the safe harbor retroactively, thus imposing liability in many past cases where the current state of the law imposes none. I wrote on retroactivity in the law some years back.
Expanding drug liability -- retroactively