Image credit: National Archives
On a Sunday afternoon in Washington, D.C., in 1859, Philip Barton Key, son of the man who wrote “The Star Spangled Banner,” stood in the park and waved his handkerchief in the air. He was attempting to signal his girlfriend, Teresa Sickles, who lived across the street, so that they could sneak out for a date.
Someone parted the curtains in a window of Sickles’ home and watched Key for a few minutes, but it was not Teresa. It was her husband Daniel, a well-known politician (at left in photo above). He continued to watch as Key attempted to call up to Teresa’s window. He had known for several weeks that Key was sleeping with his wife. Worse, his friends and neighbors had known, too.
Watching his wife’s lover calling upon her in full view of everyone on the street right in front of him, Sickles lost it. Consumed by rage, he grabbed two handguns from his bedroom and stormed out of the house, across the street and into the park. He ran up to Key, screaming, “Key, you scoundrel, you have dishonored my home. You must die. You must die! You must die!”
Sickles fired several times at Key, striking him in the leg and in the hand. Key grabbed Sickles’ lapels and the two men grappled on the ground, in full view of the homes of Washington’s elite. Sickles pulled away, stood and drew his second pistol. Key drew the only weapon he had, a pair of opera glasses, and threw them at his assailant. Sickles fired and hit Key near the groin. Falling back against a fence, Key pleaded for his life.
Sickles pointed the gun at the center of Key’s chest and fired. Key staggered away, dying a few minutes later. Sickles stepped back and looked around. At least a dozen people had witnessed the entire thing. Sickles fled and surrendered to the police a few hours later at a friend’s house, where he was charged with murder and taken to jail.
As a former Congressman, Sickles enjoyed certain perks during pre-trial detention. So many people came to wish him well that he was given use of the jailer's apartment to entertain his guests, among them Congressmen and other high-level members of the federal government. President James Buchanan did not make a visit, but did send Sickles a personal note. During this time, Sickles secured several renowned politicians as his defense attorneys, including Edwin M. Stanton, who would later become Lincoln’s Secretary of War. And the whole time he was detained, Sickles was also allowed to keep a weapon on his person.
Even though the proceedings were outrageous even by today’s standards of prime-time-ready crime and celebrity defendants, it is not Key’s murder or the unorthodox confinement for which we remember Daniel Sickles. It is for what he did next: told the court that he should be found innocent of the crime due to reasons of insanity, something that no one in America had ever done before.
Slipping Into Insanity
Insane people have been doing insane things and getting in trouble for it since the dawn of mankind. For most of that time, it’s also been possible that being insane could get you off the hook. Leniency toward a criminal who exhibited a mental illness was common in ancient Greece and Rome, and later spread throughout Europe. In the Middle Ages in England and Western Europe, the courts often either spared the insane the ordeal of a trial and simply committed them to an asylum, or found them guilty and then immediately referred the case to the king for a royal pardon.
In early America, the law often made no distinction between criminal insanity and other criminal behavior, but the courts sometimes acquitted the mentally ill because of their condition anyway. One notable case was Richard Lawrence, the unemployed house painter who was the first person charged with the attempted assassination of a U.S. president. (Lawrence believed that he was heir to the British throne and fired two pistols at Andrew Jackson because he thought the president was conspiring to keep him from claiming his kingdom.)
The M’Naghten Rules
The modern insanity defense, at least in the Western world, can be traced back to the case of Daniel M'Naghten, who believed he was the target of a conspiracy headed by the pope and the British prime minister. In 1843, M'Naghten attempted to ambush Prime Minister Robert Peel at 10 Downing Street, but attacked and killed Peel’s secretary instead.
During his trial, several psychiatrists examined M'Naghten and testified that he was delusional; the jury acquitted him by reason of insanity. Public outrage followed the verdict and prompted the House of Lords to convene a special session where they posed a series of hypothetical questions about insanity and the law to a panel of judges. The standards and principles discussed by the panel found their way into common law and became known as the M’Naghten Rules.
According to the rules, the defendant can use the insanity defense and may be acquitted if, “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 of the wrongfulness of his acts.” This standard is also known as the "right-wrong" test.
Twenty-five U.S. states still use a variation of the M’Naghten Rules for insanity defenses. Twenty states and the District of Columbia use the newer and less restrictive Model Penal Code Standard established by the American Law Institute in 1962. Under this rule, the defendant is not held criminally responsible if, “at the time of his conduct as a result of mental disease or defect the defendant lacked substantial capacity either to appreciate the criminality of his conduct or to conform his conduct to the requirements of law.” The remaining states have banned the use of the insanity defense.
The Sickles Trial
At trial, the jury was filled in on the soap opera dramatics that led up to Key’s death. The victim was the District Attorney for the capital, the son of the man who wrote the national anthem, a close friend of his killer and, according to local gossip, “the handsomest man in all Washington society.” The defendant was a well-connected Congressman from New York with a reputation as a ladies' man. He’d been censured for bringing a prostitute onto the floor of the New York State Senate, and had married his pregnant 15-year-old wife against her family’s wishes when he was 33. Despite his notoriety, Sickles and his wife had been welcomed into Washington’s most elite social circles after Daniel was elected to Congress. They became fast friends with Key, and Daniel often asked Key to escort his wife to social events whenever the congressman had to work late or was occupied with a girlfriend or one-night stand. Key and Teresa’s friendship quickly became romantic.
They tried to keep the affair secret, and Key even rented a house in a rough Washington neighborhood so they could meet in private, away from their friends and colleagues. Despite the precautions, the romance became common knowledge in Sickles and Key’s social circle. Eventually, Daniel received an anonymous letter detailing his wife’s infidelity. He confronted Teresa and forced her to write a detailed letter of confession, which she did. By the end of the month, Key was dead.
Sickles’ attorney, Edwin Stanton, argued that Sickles had been driven temporarily insane with grief by his wife’s infidelity and the embarrassing way in which he found out about it. Sickles, he argued, was not in his right mind when he attacked Key, and hence could not be held accountable for his actions. In the court of public opinion, Sickles had already been cleared, and he was applauded in coverage of the trial for striking down his deceptive friend and protecting the wives of the rest of Washington’s rich and powerful from a home wrecker. The jury followed suit and acquitted Sickles of the charges.
Immediately after the trial, Sickles forgave his wife, and undid all the goodwill he had built up among the press and public. Her betrayal had caused the death of a man, the editorials cried, and no honorable man would have taken her back. Sickles’ popularity in Washington and in New York plummeted and he had no hope of winning reelection to Congress. He returned home to New York in 1861, unemployed and disgraced.
The Civil War broke out a few months later, giving Sickles a chance at a fresh start. He took charge of an infantry brigade and fought in several battles. After a cannonball mangled his leg at Gettysburg, he retired from the army with a Medal of Honor and donated the bones from his amputated leg to the Army Medical Museum, reportedly visiting each year on the anniversary of the amputation. (The National Museum of Health and Medicine still has the bones on display today.)
Image credit: Library of Congress
Sickles went on to become the ambassador to Spain (where he earned the nickname the “Yankee King of Spain”), chairman of the New York State Monuments Commission, president of the New York State Board of Civil Service Commissioners, sheriff of New York, and was even re-elected to congress. He died of natural causes on May 3, 1914, and was buried in Arlington National Cemetery.
Since Sickles' historic plea, many famous criminals have used the insanity defense with mixed results, including Jeffrey Dahmer, John Hinckley, John Wayne Gacy, and John duPont, the multimillionaire heir to a chemical company fortune who murdered an Olympic wrestler he believed was part of an international conspiracy to kill him.
But according to the National Institute of Mental Health, the defense is invoked in less than 1% of felony cases, and is then only successful about a quarter of the time. Even if a defendant is acquitted for reasons of insanity, they are still usually institutionalized for treatment for several years or even decades.