I don't care what someone's diagnosis is. There is no excuse that justifies murdering another human being, especially your own children. I had post partum psychosis. I've been the victim of severe childhood trauma by a schizophrenic parent. There is no excuse for that was done to me and no excuse if I had, heaven forbid, hurt my own child. Just because you are mentally ill doesn't mean you suddenly have no moral compass. If you want to know where stigma comes from, it comes from situations like this. There should be only two options, not guilty (because there isn't enough evidence), or guilty but mentally ill. If you are found guilty but mentally ill, institutionalize the person for the duration of a criminal sentence. If they improve, send them to jail.