Admittedly I didn't phrase it too subtly... I was suggesting gross negligence with lethal consequences. That it is impossible to engineer everything 100% safe in the first iteration is fairly obvious, but what seems to have happened here is that they realized their mistake (they started making this part differently) and yet they did not initiate a recall.
So if the original part claims lives, after the manufacturer was aware of the problem, but decided not to address the problem for extant parts, then yes I think the manufacturer should be liable for these deaths. Additionally, the fact that they apparently did not use a new part number for the improved version gives at least the impression of wanting to sweep it under the rug.
Actually, I am opposed to capital punishment. The quip about a death sentence for corporations is meant to emphasize a kind of asymmetry about this whole corporate personhood idea, which is that proponents claim they should have all the rights and privileges of an individual person but typically remain quiet about the associated responsibility and accountability that individual persons have.
Finally, too big too fail (in terms of finances or jobs) doesn't exonerate even GM from wrongdoing -- if that is what will be determined to heve been the case here.