The Trial of John Hinckley Jr. and Its Impact on Expert Testimony

With the release of John Hickley Jr., the man who attempted to assassinate President Ronald Reagan, from the mental hospital he spent the last 35 years in, there has been renewed interest in the case that found him not guilty by reason of insanity.

Few defenses in a criminal trial require the level of expertise required of a defendant pleading not guilty by reason of insanity. The insanity defense often garners media attention during highly publicized trials. However, it is invoked less than one percent of the time, with a nationwide success rate of about 0.26 percent.

Hinckley’s trial shifted public perception to such a degree that it substantially altered the insanity defense and the expert testimony on which it relies.

On March 30, 1981, Hinckley fired gunshots that wounded President Reagan and three others. Hinckley’s federal trial began on May 4, 1982, in Washington D.C.’s District Court. He was charged with thirteen counts in connection to the assassination attempt. Born into an affluent family, Hinckley was able to afford a high-priced attorney and multiple experts. Due to the overwhelming evidence against Hinckley; a defense of not guilty by reason of insanity seemed to be the only means of an acquittal. A difficult defense in its own right, Hinckley, his parents, and his legal team crafted a strategy that relied almost exclusively on expert testimony.

A Battle of Experts: Hinckley’s Witnesses

Following the standard of the Model Penal Code test, Hinckley advanced the theory that he could not appreciate the criminality of his conduct or conform his conduct to the requirements of the law. His defense team argued that Hinckley suffered from schizophrenia and major depressive disorder. To support their theory, the defense called a number of expert witnesses to the stand to testify.

Dr. Carpenter, an expert in schizophrenia, testified that Hinckley was unable to separate reality from fiction, a symptom of the disease. Carpenter used Hinckley’s obsession with the film Taxi Driver and its lead actress Jodie Foster (whom Hinckley vehemently stalked prior to the assassination attempt), among other examples, to illustrate his incapacitated mental state. Significantly, Carpenter testified to the ultimate issue of whether Hinckley appreciated the wrongfulness of his conduct, concluding that: “[I]t is my opinion on a purely intellectual level that he didn’t know that he had that knowledge, that those were illegal acts… he was not reasoning about the legality issue itself.”

Likewise, Dr. David Bear, a psychiatrist from Harvard Medical School, had been on the witness stand for days testifying to Hinckley’s schizophrenia. Bear’s attempt to use CAT scans to prove Hinckley’s insanity was denied by the judge. It almost resulted in the doctor being held in contempt of court for his insistence on using the X-rays. But that did not prevent Bear from drawing conclusions as to Hinckley’s mental state at the time of the offense. Bear testified that Hinckley’s illness “prevented people from observing his true emotions”. And that lay witness testimony as to Hinckley’s “flow of thought” was a “terribly unreliable source.”

As was the federal standard at the time, the government was required to prove beyond a reasonable doubt that Hinckley was sane at the time of the offense. Therefore, for every expert that was called to testify on behalf of the defense; the prosecution called an expert who disagreed. This resulted in an unprecedented expenditure of resources on both sides. It was estimated that Hinckley’s trial cost totaled over $2 million, largely due to expert witness fees. Nine expert witnesses took the stand to debate Hinckley’s mental state at the time of the offense. By the time the trial concluded, the jury seemed understandably confused about the contradictory expert testimony. They took over four days to deliberate.

Ultimately, the jury acquitted Hinckley of all charges and found him not guilty by reason of insanity. For the past three decades, Hinckley has been confined to a mental hospital.

Post-Hinckley: Long-Lasting Effects on Expert Testimony and the Insanity Defense

After Hinckley’s acquittal, there was such public outrage that the laws governing the insanity defense needed to be changed immediately in response to the backlash. Within a month of Hinckley’s verdict, Congress held hearings regarding the use of the insanity defense. Within three years, half of the states enacted laws to limit the defense’s use. One state, Utah, abolished the defense completely.

On the federal level, the Insanity Defense Act of 1984 redefined the defense to apply only in cases where the defendant was “unable to appreciate the nature of the wrongfulness of his acts” at the time of the offense. Prior to the Act, at Hinckley’s trial, the standard allowed him to argue the defense if he were unable to conform his conduct to the law. Furthermore, the Act placed the burden of proof of the defendant to establish insanity by clear and convincing evidence; while also limiting the scope of expert testimony on the ultimate legal issue of the defendant’s sanity. Amended by the Act, Rule 704 of the Federal Rules of Evidence now states:

Now, no expert witness testifying with respect to the mental state or condition of a defendant in a criminal case may state an opinion or inference as to whether the defendant did or did not have the mental state or condition constituting an element of the crime charged or a defense thereto. Such ultimate issues are for the trier of fact alone.

So what does Hinckley’s trial signify for expert witness testimony regarding the insanity defense? Most importantly, Hinckley’s trial was the catalyst of legislative change. Now, expert witnesses may not testify as to the ultimate issue, which is whether a defendant was insane at the time of the offense. This restricts not only the expert witness testimony itself but also has practical limitations. Because the ultimate issue of sanity is now decided by the jury, and due to the historically low success rate of insanity defenses, both sides are more likely to reach an agreement prior to trial. Whereas prior to these changes, an insanity defense may have resulted in a “battle of the experts”. Which was seen in Hinckley’s trial. With the ultimate issue out of the hands of experts to conclude, today’s experts on both sides agree in an overwhelming majority of cases involving a claim of insanity.

While Hinckley’s impending release is likely to be a derisive public issue just like his acquittal over three decades earlier; his trial has left its mark on history and has set precedents in expert witness testimony for years to come.