Legal insanity and mental illness are two entirely different situations. Someone who is suffering a psychotic episode [a complete break from reality which may or may not include delusions, auditory and/or visual hallucinations] may be considered "criminally insane" or may be considered to have been "criminally insane; the inability to know consciously the differences between right and wrong".
Bipolar Disorder I can cause both psychosis and auditory/visual hallucinations therefore it is possible that someone with bipolar disorder could be considered "legally insane" at the time of the commission of a crime, if they were experiencing extreme psychosis.
However, it does the mentally ill a great disservice to imply that simply having a mental health condition means that person is automatically out of control, psychotic or otherwise...
Now, those who suffer from mental health issues may not be aware of the seriousness of their issues and/or may self-medicate. That is why it is imperative for close friends and/or family to observe someone with a mental health condition to ensure that they properly follow whatever regimen their psych docs provide for them, both with meds and other treatment.
That being said, your average mentally ill person is far, far more likely to be a victim of violent crime than to perpetrate one. Imagine how easy it would be to avoid criminals if they all acted "weird" or "mentally ill" all of the time.
I feel I can speak with some authority on this as not only did I minor in psych as an undergrad, I suffer from mental illness. It is so difficult for people to understand that mentally ill people suffer from a REAL condition that is usually treatable with patience and perseverence.
If you saw me walking down the street, or knew me casually [even long-term] you would likely not know that I have a history of mental illness. I am a mother, wife and business owner. I follow a strict regimen when if comes to my meds and I treat my condition just as I'd take the necessary treatment steps for diabetes or any "acceptable" illness.
And believe me, it's much safer for our society to allow those who have mental health concerns to seek treatment without becoming ostracized or excluded from society than to leave them untreated. There are many professions that basically make it impossible for someone suffering from mental illness to seek treatment because they will lose their employment. Of course, hiring a severely mentally ill person in a condition like this wouldn't be ideal but that's beside the point. People with mental illness need to be treated with the same respect, and held to the same standards as anyone else. Otherwise they avoid treatment out of shame, etc.
In my opinion, mental health issues have very little to do with this case. This woman is a mass-murderer and should suffer the consequences. If I did something like this, even when my illness was uncontrolled, I would expect to be held responsible. Just like mentally ill people should be treated equally as others with health conditions in a medical setting; the same should apply to the legal setting. The only exception being some type of extreme psychosis that had not been caused by extraneous circumstances [i.e. drug abuse, non-compliance with meds, etc.]
I hope this makes sense. I'm sleepy... and don't worry I won't be taking Ambien and driving off anywhere. They gave my Ambien when I was in the hospital for bed-rest during pregnancy with preeclampsia, to help me sleep ONCE. About 25-30 minutes later, the blankets appeared to be rolling in waves toward me and the walls began undulating. It is, thankfully, the only time I've hallucinated and it was awful. Being 7 months pregnancy and tripping, stuck in the hospital, in a dark room alone is NOT a fun experience!!!