In 1981, President Ronald Reagan was shot by John Hinckley. Hinckley had incorporated scenes from a popular movie ( Taxi Driver) into his delusional system and was attempting to gain the love of a famous actress (Jodie Foster). He was found NGRI under the impulse control part of the ALI law, which led to hospitalization rather than imprisonment. Immediately, the federal government, and many states, tightened the insanity laws back to those of 1843 England.
Current Legal Requirements
Currently, the requirements for insanity vary by state. The typical standards require that a person be unable to differentiate between right and wrong at the time of the crime. The inability to appreciate the wrongfulness of conduct must be the direct result of a mental disease or defect. Such defects typically include psychotic disorders, mood disorders and organic conditions such as mental retardation. Virtually no state allows sociopathy to be grounds for an NGRI defense, and voluntary intoxication cannot by itself end culpability. Only a few states still contain the volitional question.
At the federal level, the Supreme Court, in USC Title 18, Chap 1, Sec 17, stated:
It is an affirmative defense to a prosecution under any Federal statute that, at the time of the commission of the acts constituting the offense, the defendant, as a result of a severe mental disease or defect, was unable to appreciate the nature and quality or the wrongfulness of his acts. Mental disease or defect does not otherwise constitute a defense.
Some states have another legal option aside from insanity: guilty but mentally ill (GBMI). On its face, this seems to be a good idea, as jurors have several options. However, there are two inherent problems. First, juries have two choices that find a person guilty, but only one that finds them innocent, leading away from giving the benefit of doubt to the defendant. Additionally, the GBMI finding assumes that prisons will engage in the same level of treatment as a hospital, so that a defendant can be equally well-served in either setting. A GBMI finding also yields a set sentence, which the person will serve even if completely psychiatrically stabilized. Alternatively, the defendant may have to be released even if they are still ill.
Loopholes and Pitfalls
The existence of an insanity defense has always been controversial. There have been several attempts to "eliminate the loophole" and thereby force mentally ill individuals into prison. Several state decisions have noted that criminal intent is an absolutely necessary part of any crime. In recent years, some states have redefined their laws to focus more tightly on the mens rea, or guilty mind. Under those laws, a person must, as a result of a mental illness, lack the ability to willingly or knowingly commit an act. This looks at criminal intent, rather than psychiatric diagnoses, therefore claiming an end to criminals getting off free.
Of course, as previously noted, the truth is that there is no evidence to suggest that this defense has ever been widely misused. A minority of states (Montana, Idaho, Utah, Kansas and Nevada) have omitted the insanity defense per se entirely, instead allowing mental state to be raised only as a mitigating factor.
Some people favor the abolition of the insanity defense for reasons unrelated to political gain. They argue that far too often (certainly in our experience) a person who is chronically mentally ill is automatically found NGRI, even when the evidence would not convict them of a crime (Halpern, 1992). In addition, some critics see it as a simple plea bargain that saves time for the lawyers and judges and locks up a possibly innocent person for many years.