It should come as no surprise to anyone that the criminal defense attorney for the alleged Ft. Hood killer has reportedly announced that his client may offer an insanity defense to the murder charges against him. After all, he has limited options, doesn't he?
But without judging that particular case, please let me explain why, in most cases, in my opinion, insanity is a lousy defense to offer to a criminal charge. First of all, by offering this affirmative defense, a defendant is essentially required to admit that he has committed the acts in question--in this case, murder. And that's certainly not going to make jurors want to let you go, is it?
But the real problem with insanity as a defense also lies in what the defense must show at trial in order to prevail. First of all, you must understand that there is a big difference between medical insanity and legal insanity. In other words, many of us may have (medically) insane relatives, out there walking around, who fail to meet the legal test of insanity! For example, the State of Georgia subscribes, in large part, to the old M'Naughten Rule of insanity. This is also known as the "right-wrong" test of insanity. In short, in Georgia, (reducing this test to its simplest terms), a defendant must carry a heavy burden of convincing a jury that he was so crazy, when he committed the crime, that he couldn't even tell the difference between right and wrong. This is a very heavy burden! As a result, it is almost impossible for most defendants to ever win with this trial defense, because even the sickest individuals generally know the difference between right and wrong!
Finally, as one old judge once observed about a bank robber, "If he was really insane, then why didn't he use a banana instead of a gun to rob the bank?"