Their action becomes rather that of a lay commission condemning the prisoner to hard labor for life on the ground that he is medically insane.
Assuming that the jury take the defence seriously, there is only one class of cases where, in the writer's opinion, they follow the legal test as laid down by the court--that is to say, in cases of extreme brutality.

Here they hold the prisoner to the letter of the law, and the more abhorrent the crime (even where its nature might indicate to a physician that the accused was the victim of some sort of mania) the less likely they are to acquit.

The writer has prosecuted perhaps a dozen homicide and other cases where the defence was insanity.

In his own experience he has known of no acquittal.

In several instances the defendants were undoubtedly insane, but, strictly speaking, probably vaguely knew the nature and quality of their acts and that they were wrong.