Now, two and a half years after that highly publicized crime, a high profile trial is about to start with the defendant employing the insanity defense.
There are many myths about the insanity defense. A lot of people think it's a cop out - just claim you're mentally ill and you won't have to go to prison. In fact, the insanity defense is incredibly difficult to prove, so much so that it's very rarely used.
The most famous case of the insanity defense in the U.S. is the shooting of President Reagan in 1981. The attacker, John Hinckley, was found not guilty by reason of insanity and the jury verdict sparked such outrage that many states tightened up their laws to make it more difficult to employ that defense.
"It's pretty clear that there's this myth that the insanity defense is abused." John Jay professor Stuart Kirschner said.
But Kirschner did a study in New York and found that from 1988 to 1997, out of just over 96,000 people indicted for felonies, only 96 entered an insanity plea and only 4 succeeded in a jury trial. Those are tough odds for David Tarloff, who will go on trial early next week for stabbing to death therapist Kathryn Faughey at her Upper East Side office two and a half years ago.
The law in New York State has shifted the burden of proof from the prosecution to the defense. Previously, prosecutors had to prove a defendant was sane beyond a reasonable doubt, but now the onus is on the defense to convince a jury by a preponderance of evidence that the defendant was insane at the time of the crime.
Tarleff had been in and out of psychiatric hospitals for years at the time of the murder.
"He had been hospitalized 20 times," attorney Bryan Konoski said.
But to succeed, Tarloff's attorney will have to prove his client lacked substantial capacity to know or appreciate either the nature and the consequences of his conduct or that it was wrong.
"Meaning did the person know that he had a knife? that this knife could inflict injury or death? If the person knew that, then the next question is: did the person know that his conduct was wrong or appreciate that the conduct was wrong?" Konoski said.
Prosecutors are expected to argue that Tarloff knew exactly what he was doing and that it was wrong. Surveillance video shows where he's carrying a bag full of knives thru the lobby.
Prosecutors also say he planned to rob another therapist in the office who was injured trying to come to Faughey's aid.
Another twist came on Friday when an attorney representing Tarloff said his client refused to return to the courtroom during jury selection and refused to speak to him.
On Monday, doctors will evaluate Tarloff. They may determine he is unfit for trial and bring the proceedings to a halt.
Even if Tarloff is found not guilty by reason of insanity, he will likely spend the rest of his life in a mental hospital. Studies have shown that people hospitalized as the result of this type of verdict spend as much time in the psychiatric system as they would if they were convicted and sent to prison.
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