<P> In the United States, a criminal defendant may plead insanity in federal court, and in the state courts of every state except for Idaho, Kansas, Montana, and Utah . However, defendants in states that disallow the insanity defense may still be able to demonstrate that a defendant was not capable of forming intent to commit a crime as a result of mental illness . </P> <P> Each state and the federal court system currently uses one of the following "tests" to define insanity for purposes of the insanity defense . Over its decades of use the definition of insanity has been modified by statute, with changes to the availability of the insanity defense, what constitutes legal insanity whether the prosecutor or defendant has the burden of proof, the standard of proof required at trial, trial procedures, and to commitment and release procedures for defendants who have been acquitted based on a finding of insanity . </P> <P> The guidelines for the M'Naghten Rules, state, inter alia, and evaluating the criminal responsibility for defendants claiming to be insane were settled in the British courts in the case of Daniel M'Naghten in 1843 . M'Naghten was a Scottish woodcutter who killed the secretary to the prime minister, Edward Drummond, in a botched attempt to assassinate the prime minister himself . M'Naghten apparently believed that the prime minister was the architect of the myriad of personal and financial misfortunes that had befallen him . During his trial, nine witnesses testified to the fact that he was insane, and the jury acquitted him, finding him "not guilty by reason of insanity ." </P> <P> The House of Lords asked the judges of the common law courts to answer five questions on insanity as a criminal defence, and the formulation that emerged from their review--that a defendant should not be held responsible for his actions only if, as a result of his mental disease or defect, he (i) did not know that his act would be wrong; or (ii) did not understand the nature and quality of his actions--became the basis of the law governing legal responsibility in cases of insanity in England . Under the rules, loss of control because of mental illness was no defense . The M'Naghten rule was embraced with almost no modification by American courts and legislatures for more than 100 years, until the mid-20th century . </P>

Who was the first person found not guilty by reason of insanity