Contributory negligence was, historically, a harsh doctrine, holding that a plaintiff would be barred any recovery if he was the slightest bit negligent. Thus a person one percent at fault could be denied recovery against a party whose negligence was 99 percent to blame for the injury.
Michigan, like most other states, has now replaced contributory negligence with comparative negligence.  Under the latter doctrine, the plaintiff’s recovery is reduced only by that percentage of the accident cased by his own negligence. As a practical matter, this change clearly increases corporate liability and, therefore, insurance rates. However, it would not seem to have any effect on the broader insurance functions of accepting and determining risks, and it is hard to argue with this change from a standpoint of justice.
Unfortunately, this clear expansion of liability is exacerbated by the refusal of the legislature to extend the same concept of proportional liability to defendants under joint and several liability. Plaintiffs are no longer precluded, by their own negligence, from collecting damages for that part of the accident for which the defendants are at fault. They are expected to bear only that portion of the loss caused by their negligence. Defendants, however, operating under joint and several liability, must still pick up the cost of damages caused by other defendants unable to pay their share. Thus comparative negligence, without a corresponding shift on the defendant’s side, hit defendants from both sides, further pushing up liability costs.