This right here is their culpability. Michigan State law is clear and the parents broke the law. It doesn't matter if all the other kids are doing it too. They haven't gone out and murdered a bunch of people.

Some laws don't get policed, as in pursued, until a crisis happens.

You're still raponsible for outcomes when you break the law. In this case, it was multiple homicide.

Still, the prosecution has handed the mother grounds for appeal, especially if it turns out that it was the father who gifted that gun against her objections and he either fets off or gets a markedly lighter sentence.

They should have been tried together.