You are so kind

Joint and several liability started in a case (forgot the name) when three guys went hunting, the two guys from each side fired a shot toward the victim, who was in the middle. The victim suffered a injury in his face. The court could not determine who did it, although if it happened today, forensic analysis could easily determine exactly which guy fired the injurious shot. At the time it was not available so the judge said, well, I am going to place the burden of proof on you guys to figure out who did it. If you can't, I am going to hold both of you liable and that was what the judge did. Most time in today's life you will hear a case that a patitent is administered a certain drug and developed bad syndrome. It will be a generic drug so that it is really impossible to figure out whose product it was, especially when it happened many years ago. Some courts will hold all the manufacturers liable and share the damage. If there are hundreds of manufacturers then obviously it is impossible to name all of them defendants. All the plaintiff has to do is to name a few big ones and let them share the responsibility.