Prior to yesterday’s revelation that Holmes was in treatment with a psychiatrist specializing in schizophrenia, the common wisdom on the case was that Holmes would have to plead not guilty by reason of insanity and that the plea would have little chance of success.
That was because under Colorado law a person is legally insane if the person suffers from a mental disease or defect that makes the person incapable of distinguishing right from wrong. The legal and mental health experts opined that it would be difficult first to prove that Holmes suffered from a mental disease and second that the disease prevented him from knowing the difference between right and wrong. How could he not know that picking up a gun and shooting people in a theater was wrong? One expert wondered.
Well, we have the answer now. If Holmes had been diagnosed as schizophrenic, the insanity path is a lot less difficult. Schizophrenia is a form of psychosis in which, as one person put it, the person interprets reality different than we do. More succinctly, a person suffering from schizophrenia is subject to hallucinations and delusions. He might hear voices in his head telling him what to do. He has trouble telling what is real and what is not real. The reality in his head is not the same as the reality outside his head. If his reality did not contain a definition of right or wrong, or if he was in the grip of a hallucination so powerful and complete that there simply were no moral distinctions, then he would seem to be legally insane under our definition. Suppose, for example that in his hallucination he was commanded by voices to kill the people in the theater, and suppose that these voices were the source of what was right, would he be legally insane and therefor not responsible?
The fact that he planned the killing meticulously for four months beforehand does not necessarily diminish this defense. Schizophrenia is not a mental disease that pops up in a flash; it is a permanent condition. All of this planning activity could have been undertaken in the same delusional state.
And don’t forget that under Colorado law the defendant is not required to prove he is insane. After the defense is raised, the state must then prove he was in fact sane at the time the crime was committed. With a diagnosis of schizophrenia on the table, this could be an extremely difficult task. 
As RD Laing said, schizophrenia is the result of a lifetime of social abuse. He said the very label itself constitutes a horrific abuse which actually worsens the psychosis. This is because it implies being capable of extreme violence without ANY PROVOCATION WHATSOEVER. Being aware of this connotation the patient become terrified of losing his or her mind and going berserk. He or she sees conspiracies everywhere because EVERYONE denies the abuse. They’ve all bent over backward to help the ungrateful bastard, toiled till their fingers bled. The word LOVE is bandied about like nowhere else on Earth. Accusations of sexual abuse by the patient get met with such howls of indignation. How could this vile, evil individual deliberately invent such dreadfully hurtful lies. MAD and BAD, an ABOMINATION of filth. Because the side effects of antipsychotics are so extreme, the patient believes that he or she is being DELIBERATELY poisoned by the state. (No wonder being so bloody toxic, the patient that is.)
The dogma that schizophrenia is inherited suits the abusers, including the state as it gets everyone off the hook, blame the perpetrator of a massacre as EVIL. As long as this self serving delusion persists, massacres will persist and if anything just get worse. Just a comment like this is seen as a provocation to more massacres. How will the death penalty deter a massacre if the potential perpetrator is going to commit suicide anyway. In this case it is just an incitement to take out as many people as possible to avenge a lifetime of abuse. Wake up America. You are extremely ill.
Paul, I’m sorry but you are misinformed. The psychological evidence that schizophrenia is a genetically inherited disorder is overwhelming and incontrovertible. For instance, when identical twins are adopted by different families at birth and reared apart, if one develops schizophrenia there is a 50% likelihood that the other one will also develop schizophrenia. We also have been able to identify specific genetic markers in DNA analysis that are known to be associated with schizophrenia. In contrast to PTSD, there is absolutely no empirical evidence showing that extreme psychological trauma can trigger schizophrenia. These are important social problems, but making uneducated judgments about a psychopathology you clearly know nothing about is irresponsible.