At 10AM on August 23, 1973, Jan-Erik Olsson, a convict on leave from prison, walked into the Kreditbanken Norrmalmstorg bank in Stockholm, Sweden. Dressed in a wig with his face painted black, as he entered the bank lobby he pulled a submachine gun from under his coat, fired into the air, and yelled out: “The party has just begun!” Thus began the most infamous bank robbery in Swedish history, an event which kept Swedes glued to their television sets for six tense days and gave us us the name of a well-known but controversial psychological condition: Stockholm syndrome.

Within minutes of Olsson’s arrival the police surrounded the bank, with Criminal Inspector Ingemar Warpefeldt being the first to enter. But he was immediately shot in the arm by Olsson, who at gunpoint ordered him to sit in a chair and “sing something.” As Warpefeldt sang “Lonesome Cowboy” by Elvis Presley, the police sent in another officer, Inspector Morgan Rylander, to act as a go-between between Olsson and the authorities. It was then that Olsson made his demands, asking for three million Kronor in cash, two pistols and bulletproof vests, a fast getaway car, and free passage out of Stockholm. He also demanded that his friend and fellow bank robber Clark Olofsson be released from prison and brought to the bank. To ensure that the police complied with his demands, Olsson rounded up four bank employees – Birgitta Lundblad, Elisabeth Oldgren, Kristin Ehnmark, and Sven Safstrom – and held them hostage in the bank vault.

What followed was a tense and surreal six-day standoff as the police scrambled to find a way to take down Olsson while still appearing to comply with his demands. Late on the first day they delivered the money along with Olofsson and the car, but when they forbade the robbers from leaving with the hostages Olsson and Olofsson chose to remain barricaded in the vault. Meanwhile ordinary Swedish citizens, enthralled by the spectacle playing out on live television, called the police and suggested all sorts of harebrained rescue schemes, from bringing in a Salvation Army choir to sing religious songs to filling the vault with tennis balls to immobilize the robbers to releasing a swarm of bees into the bank. On the third day the police managed to drill through the roof of the vault and snap a photo of the robbers and hostages inside, but were swiftly repelled when Olofsson shot an officer through the hole. Finally, on the night of August 28, six days into the crisis, the police pumped tear gas into the vault and forced the robbers to surrender.

Then, something strange happened. When the police called for the hostages to exit the vault first, they refused, with Kristin Ehnmark crying out: “No, Jan and Clark go first—you’ll gun them down if we do!” 

Once outside the vault, the robbers and hostages embraced, kissed and shook hands, and as the police dragged Olsson and Olofsson away, Enmark pleaded: “Don’t hurt them—they didn’t harm us.”

In the days that followed it became increasingly clear that the hostages had formed a strangely close personal bond with their captors. Despite threatening to the police many times to execute them, Olsson and Olofsson treated the hostages with remarkable kindness. Olsson gave Kristen Enmark his coat when she began to shiver, consoled her when she had a bad dream, and even gave her a bullet as a keepsake; and when Elisabeth Oldgren complained of claustrophobia he allowed her to walk around the bank lobby tied to a 30-foot rope. Such acts of kindness endeared the hostages to their captors, and within a day everyone was on a first-name basis. As hostage Sven Safstrom later recalled: “When he treated us well, we could think of him as an emergency God.”  

Indeed, according to Ehnmark, the hostages soon came to fear and hate the police and government than their captors, accusing them of gambling with their lives by drawing out the siege: “We [were] more afraid of the policemen than these two boys. We [were] discussing, and, believe it or not, having a rather good time [there]. Why can’t they let the boys drive off with us in the car?”

Ehmnark even phoned Swedish Prime Minister Olof Palme, imploring him to let the robbers take the hostages with them in the getaway car: “I think you are sitting there playing checkers with our lives. I fully trust Clark and the robber. I am not desperate. They haven’t done a thing to us. On the contrary, they have been very nice. But, you know, Olof, what I am scared of is that the police will attack and cause us to die.”

In another incredible show of compassion for her captors, when Olsson threatened to shoot Sven Safstrom in the leg to shake up the police, Ehnmark actually urged her colleague to take the shot.

The authorities suspected early on that something strange was going on when the Police Commissioner was allowed into the vault to check on the hostages’ health, only to find them hostile to him but relaxed and jovial with the robbers. Microphones placed in the hole in the vault roof also picked up the sounds of hostages and captors joking and laughing together. Indeed, it was this which convinced the police that tear gas could be used without fear of the robbers harming the hostages.

In the wake of the robbery, criminal psychiatrist Nils Bejerot, who had advised the police during the crisis, interviewed the hostages, many of whom continued to visit their captors in prison for many years afterward. Bejerot coined the term Norrmalmstorgssyndromet or “Norrmalmstorg Syndrome” to describe this apparently contradictory phenomenon. This soon became known in outside Sweden as “Stockholm Syndrome.” 

But while the term was coined in 1973, it would gain widespread use until three years later. On February 4, 1974, Patty Hearst, the 19-year-old heiress to the Hearst publishing fortune, was kidnapped from her Berkeley apartment by the Symbionese Liberation Army or SLA, a left-wing urban guerrilla group. After ransom negotiations broke down, the SLA kept Hearst bound and blindfolded in a closet for months, forcing her to memorize left-wing literature on pain of death. As Hearst later testified: “[Donald] DeFreeze told me that the war council had decided or was thinking about killing me or me staying with them, and that I better start thinking about that as a possibility. I accommodated my thoughts to coincide with theirs.”

On April 15, two months after the kidnapping, Hearst suddenly reappeared while carrying out the armed robbery of the Sunset District Hibernia Bank in San Fransisco, identifying herself as “Tania.” Over the next year and a half Hearst participated in a number of SLA actions including another bank robbery and the attempted murder of two police officers before being arrested on September 18, 1975. While being booked, Hearst gave her occupation as “urban guerrilla.”

Hearst’s trial, which began on January 15, was a landmark case in criminal liability, with her attorney, F. Lee Bailey, arguing that she had been brainwashed by the SLA and was suffering from Stockholm syndrome – bringing the newly-invented term to the public consciousness for the first time. According to US criminal law, in the absence of a diagnosed mental illness a person is considered fully responsible for any criminal action not committed under duress. Security footage of the Hibernia Bank robbery showed no sign of Hearst acting against her will, and while a post-arrest psychiatric evaluation uncovered signs of extreme mental trauma including a significant IQ drop, nightmares, and memory loss, she did not appear to be suffering from any discernible mental illness. Thus for her to be acquitted on grounds of brainwashing would have been unprecedented in US legal history.

Unfortunately, by demonstrating numerous instances where Hearst could easily have contacted the authorities and escaped the SLA, the prosecution managed to convince the jury that she had joined the group willingly, and Hearst was convicted of armed robbery and sentenced to 35 years in prison. She served 22 months before her sentence was commuted by President Jimmy Carter, and was later granted a full pardon by Bill Clinton in 2001.

Another famous case involving Stockholm syndrome is that of Natascha Kampusch, an Austrian girl who was kidnapped in 1998 at the age of 10  by Wolfgang Prikopil and held in a cellar for 8 years. On the day Kampusch escaped, Pikopil, knowing the police were after him, committed suicide by jumping in front of a train. When Kampusch learned that her captor had died, she reportedly wept inconsolably and later lit a candle for him as hid body lay in the morgue.

According to psychiatrist Dr. Frank Ochberg, who helped define the phenomenon for the FBI and Scotland Yard in the 1970s, Stockholm syndrome develops as part of a coping strategy that helps captors adapt to a highly-stressful situation: “First people experience something terrifying that just comes at them out of the blue. They are certain they are going to die.

Then they experience a type of infantilization – where, like a child, they are unable to eat, speak or go to the toilet without permission. Small acts of kindness prompt a primitive gratitude for the gift of life.

The hostages experience a powerful, primitive positive feeling towards their captor. They are in denial that this is the person who put them in that situation. In their mind, they think this is the person who is going to let them live.”

This process is similar to the techniques allegedly used by China and North Korea to “brainwash” captured American servicemen during the Korean War. According to survivor testimony, prisoners were first tortured and deprived of sleep and food in order to break their will. They were then made to perform small tasks for their captors such as delivering mail or food, building a relationship of trust between captive and captor. These tasks grew progressively antithetical to the prisoner’s own worldview, such as writing or broadcasting anti-American propaganda, until the prisoner came to sympathize with his captor’s cause. As in the case of Patty Hearst, the prisoners adapted their thinking in order to survive.

However, despite its ubiquity in popular culture, actual instances of Stockholm syndrome are rare, and many psychiatrists don’t accept that it exists at all. According to High McGowan, a hostage negotiator for the NYPD for 35 years: “I would be hard pressed to say that it exists. Sometimes in the field of psychology people are looking for cause and effect when it isn’t there. Stockholm was a unique situation. It occurred at around the time when we were starting to see more hostage situations and maybe people didn’t want to take away something that we might see again.”

Indeed, Stockholm syndrome is not an official psychiatric diagnosis and does not appear in the American Diagnostic and Statistical Manual, the International Statistical Classification of Diseases and Related Health Problems (ICD) manual or other commonly-used diagnostic texts. According to Oxford University psychologist Jennifer Wild, what is commonly referred to as Stockholm syndrome may in fact be an amalgamation of other, more common psychological phenomena that present in extreme circumstances: “A classic example is domestic violence, when someone – typically a woman – has a sense of dependency on her partner and stays with him. She might feel empathy rather than anger. Child abuse is another one – when parents emotionally or physically abuse their children, but the child is protective towards them and either doesn’t speak about it or lies about it.”

Others argue that the whole concept of Stockholm syndrome is inherently sexist, as nearly all reported sufferers are women. The implication of the label, they argue, is that women are less resilient than men and that empathizing with kidnapper is a sign of inherent weakness. But according to American Journalist Daniel Lang, who interviewed the participants of the Normmalmstorg Robbery for the New Yorker, this view ignores a vital dimension of hostage-captor relations:

“I learned that the psychiatrists I interviewed had left out something: victims might identify with aggressors as the doctors claimed, but things weren’t all one way. Olsson spoke harshly. ‘It was the hostages’ fault,’ he said. ‘They did everything I told them to do. If they hadn’t, I might not be here now. Why didn’t any of them attack me? They made it hard to kill. They made us go on living together day after day, like goats, in that filth. There was nothing to do but get to know each other.’”

Many alleged sufferers also reject the label, including Natascha Kampusch, who stated in a 2010 interview: “I find it very natural that you would adapt yourself to identify with your kidnapper. Especially if you spend a great deal of time with that person. It’s about empathy, communication. Looking for normality within the framework of a crime is not a syndrome. It is a survival strategy.”

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