Unsolved Mysteries: The Murder of Catrine da Costa and the Show Trial That Followed

Known in Sweden As the ‘Cutting Up Murder’, It Is a Blunt Name for Sweden’s Most Horrific Unsolved Case

Michael East
Dec 15, 2020 · 13 min read

There are many types of murder and many differing reactions to the circumstances surrounding them. While all killings go rightfully condemned, some go beyond this natural reaction and bring about feelings of extreme revulsion and disgust. These crimes are those that stand out for their brutality and the callousness of the criminal behind them. One such murder is that of Catrine da Costa. The killing is so horrific that it opened up new discourse in Sweden about the way women were treated, being the inspiration behind the publication of Steig Larsson’s famous The Girl with the Dragon Tattoo, entitled Men Who Hate Women in Sweden. The case is one where the value of truth seemingly abandoned Sweden, with no justice to be found for Catrine, nor the two men accused of her murder.

Catrine da Costa was born on June 19, 1956, and worked as a prostitute in Stockholm. She had tragically become addicted to heroin while still in high school and became homeless soon afterwards. To fund her habit she turned to prostitution. Her life had almost turned around in 1979 when she moved to Portugal and married a local man, the couple having a son together. However, she couldn’t kick her addiction to heroin and she was sent back to Sweden, being forced again to work at Malmskillnadsgatan in the red light district. She was attractive, dark-haired and freckled, yet with the ravages of the drugs beginning to show on her young face. By 1984 her habit was getting worse, and to fund her increasing needs she turned to accepting clients that were known to be dangerous. It was sometime during the Pentecost celebrations of June 10, 1984, a public holiday in Sweden, that Catrine would disappear, being last seen when she exited the vehicle of a man in the red-light area. Her mother raised the alarm after not hearing from her, and every parents’ worst nightmare would soon be confirmed.

Parts of Catrine da Costa’s dismembered body were found in plastic bags at Talludden in Stockholm in 1984. | Expressen

On July 18, parts of a dismembered body were discovered underneath a bridge at Karlberg’s beach in Solna, just north of the Stockholm City Centre. They were dumped in a bin bag. Other body parts were discovered on August 7. At the scene, strands of hair and a blue towel were found alongside the bag containing the remains. Nobody knew how long it had been there. The body was identified as belonging to da Costa through fingerprints and the condition of the remains meant that no cause of death could be ascertained. Her head, internal organs, one breast and her genitalia, were never recovered.

The media and public were outraged at the circumstances of the crime. While the killing of prostitutes is not unknown in the country, the bloody and visceral horror of the dismemberment, coupled with the callous discarding of the remains as if trash, led to an outpouring of anger from the media, campaigners and activists alike. Feminist campaigners organised rallies and protests against violence, circulating petitions and making regular television appearances following the killing. The pressure for results was undoubtedly now on Stockholm Police.

The Karolinska Institute | Sinikka Halme, Wikimedia Commons, CC BY-SA 4.0

Soon after the discovery of the remains, eyes turned toward a pathologist at the Department of Forensic Medicine at the Karolinska Institute, the first set of remains being found close by. Dr Teet Härm was known to use prostitutes and view violent pornography, being considered “creepy” by former colleagues. He sent unsolicited autopsy reports to his friends, complete with graphic photographs, and even invited these friends to watch him perform autopsies. Despite this, he was seen as one of the upcoming lights in his field, already being widely published at 30 years of age and speaking at several international conferences. His specialisation was strangulation, and he was considered an expert on sexual violence. Two years before the killing of Catrine da Costa, Härm’s wife, Ann-Catherine, had been found hanged in their bedroom.

While the case had at the time been ruled a suicide, there was some suspicion by police working on the matter that it may have been a murder. The deceased was dressed for a night out and in the process of divorcing her husband. Ann-Catherine had been found hanging from the side of their bed with a ligature around her neck. Just two months later, Härm published his first paper on strangulation. Police noted that he seemed unusual and callous after his wife’s death, being seen as cold and arrogant by many in his life. However, given the nature of his work, it is not unreasonable to suggest he may have assumed a detached persona, and his personal manner should have no bearing on the facts of the case. The matter officially remained a suicide.

The nature of the dismemberment led investigators to believe a medical man was involved, with Härm’s own supervisor Jovan Rajs concluding that the killer was skilled in human dismemberment rather than animal dismemberment, ruling out the possibility of a butcher or other animal worker. Härm was arrested after Ann-Catherine’s father reported his suspicions to the police. Showing his photo around the red light district, 50 separate women recognised him, with one saying he had been violent toward her. During questioning, he lied about how often he used prostitutes, claiming there had only been one incident while interviews in Malmskillnadsgatan suggested otherwise. Despite suspicions, no physical evidence linking him to the crime was found, and he was released five days later. Later that year he would attempt suicide, losing much of his hearing in the process. While he was not named in the Swedish press, many knew his identity and his former mother-in-law, Ann-Catherine’s mother, was employed by the tabloid Expressen. The newspaper was front and centre of the campaign against him, portraying the suspect as akin to Hannibal Lecter.

At this same time, Dr Thomas Allgen, a GP, was reported to police by his wife on a seemingly unrelated matter. Allgen’s wife Christina accused her husband of child sex abuse, claiming that he had molested their 17-month old daughter. At the time, the Allgens were going through a nasty divorce and examinations revealed no evidence of molestation. The couple would separate later that year.

There was little movement in the case for some time, it being 1985 before police believed that a break had finally come. It was revealed that Teet Härm and Thomas Allgen were partially known to each other, having worked together for 18 months between 1980 and 1981. Allgen allegedly even invited Härm and his then-girlfriend to his home for dinner. Once Christina realised that Härm was the individual being talked about as a suspect in the press, she made a phone call to Stockholm police asking if the man was indeed Härm. They shockingly confirmed it was so. She soon made a new accusation against her now ex-husband, claiming that her daughter was saying she had witnessed a dismemberment. The police came to the conclusion that the two men must have been jointly involved in the killing of Catrine da Costa. However, on February 28, 1986, the Swedish Prime Minister Olof Palme was assassinated in the street near his central Stockholm home, and all police resources were diverted to the hunt for his killer. The assassination would go unsolved, with thousands of man-hours devoted to the killing.

Further evidence would begin to mount against the pair in the autumn of 1987. The owners of a photo shop close to the Karolinska Institute claimed that in the summer of 1984 two men had sought to process a film at their shop. They alleged that this film contained images of a corpse first decapitated and then dismembered. They claimed they didn’t alert the police as the two men had said the pictures were part of a top-secret investigation. Crucially, they picked out Allgen in a line-up, being less sure of Härm. Police believed they had enough evidence to convict the two men on a murder charge and they were arrested in October. They went to trial in January of 1988.

The killing was a press sensation | TV4

The trial of Härm and Allgen was a media sensation. The killing had already drawn broad interest and revulsion, and the indictment against two respectable middle-class doctors only added to the public furore. The prosecution alleged that the two men murdered her in the laboratory at the Karolinska Institute before cutting her up using the facilities usually used for forensic medicine. The defence contended however that the evidence of a child who had been 18-months-old at the time was unsafe, with Allgen’s ex-wife having “interpreted” what she was initially being told and child psychologists having behaved unethically afterwards. The mother is quoted as saying her child told her at the time that “they threw the head away.. and then the lady was chopped up.”

However, the evidence of Allgen’s daughter was not the total of the case against him and Härm, with the photograph shop owners giving evidence alongside other witnesses that placed Härm in the company of da Costa. One stating that they had seen both men together with the child at the Department of Forensic Medicine, despite the two men claiming not to have seen each other for two years. Why Allgen would take his daughter to a murder and attempt to develop a film containing evidence, was not explained, with these hardly seeming to be the actions of two knowledgeable individuals. Working at a laboratory, Härm would have almost certainly have had private photographic facilities he could have utilised had the men been seeking a trophy.

However, primarily from the evidence of Thomas Allgen’s then 5-year-old daughter, both Härm and Allgen were found guilty of killing Catrine da Costa.

Protest calling for justice for “Justice For Catrine”, 1991 | Expressen

There was a feeling amongst many that the integrity of the trial had given way to activist pressure and the sensationalism of the tabloid press. This would have dire consequences when jurors were interviewed in the Swedish daily newspaper Aftonbladet, commenting on the decisions of the court. The High Court had no choice but to declare a mistrial, both suspects being free to go. The decision was portrayed as another example of men getting away with violence, others suggesting that their social status and well placed links had ensured they walked away. Public and media pressure once again came to bare and a second trial was arranged.

At the second trial, the Swedish National Board of Health and Welfare were tasked with ascertaining the victim’s cause of death and, given the poor condition of the remains, they couldn’t say with 100% certainty that Catrine da Costa had indeed been murdered. While the press would portray the decision as absurd given the dismemberment, it is essential to remember that the balance of justice rests on a verdict being beyond a reasonable doubt. With no actual evidence the victim had been murdered, Härm and Allgen were acquitted of the murder charge. At the same time, the judge believed the testimony of Allgen’s daughter, finding the duo had indeed dismembered her body. The statute of limitations on this charge had already expired.

The consequences of the trial wouldn’t end there for Härm and Allgen with both men barred from practising in May of 1989. Successive appeals by the men to the Supreme Court of Sweden, the Supreme Administrative Court of Sweden and the European Court of Human Rights have failed to overturn the ruling. Compensation claims from the duo have also been dismissed. The outcome of the trial would divide Sweden, with many believing that the two men got away with murder. However, subsequent years and new investigations by the press and crime writers have led most to now think that the entire indictment had been the worst miscarriage of justice ever seen in Scandinavia.

Tributes are left in the memory of Catrine da Costa, 1991 | Expressen

There was never a single piece of physical evidence to fit either man to the crime, and much of the suspicion seems to have been fuelled by personal vendettas. That being from the family of Härm’s deceased wife Ann-Catherine and the wife of Allgen. These accusations, coupled with political activism and sordid details of the men’s private life, in particular, Härm’s frequenting of prostitutes and “creepy” nature, caused a perfect storm of a media sensation, creating a sense of hysteria and moral panic around the case that ended in a show trial. Indeed, the main piece of evidence against the men was based on the testimony of a five-year-old child that many believe had been unduly led by her mother, creating false memory syndrome. Individuals being able to carry false memories and the role that external influence can play in their formation is widely accepted by scientists.

Often left out of retellings is claims from Allgen’s ex-wife that his daughter had also spoken of ritual murder, cannibalism, homosexual intercourse and grilling of heads, suggesting other doctors were also involved in a conspiracy and cult. These fantastical claims are seemingly influenced by widespread moral panics in the 1980s surrounding Satanic Ritual Abuse, the majority of which has since been widely debunked. Tape recordings of conversations with the child reveal that she said nothing which would independently be considered an accusation, with her responses being interpreted by her mother. Following the case, Allgen was separated from his child permanently.

“The child was only 18 months old when she was supposed to witness the cutting up, and yet she was supposed to be able to, some two years later, give credible evidence to child psychologists that is used against the doctors in court? Unbelievable.”

An expert on the case, Professor Lennart Sjöberg, Stockholm University, Telegraph

Leif GW Persson | IMDB

Leif GW Persson, the widely respected author and head of research at the Swedish National Police Board, agrees that the two men were innocent. Persson has advised the police for forty years and was involved in the Catrine da Costa killing from the beginning. He would describe the investigation as “one of the worst murder investigations I have seen.”

“When I first heard about the case and the apprehension of Teet Härm, I was sceptical. I spent thousands of hours studying this investigation, and I am convinced that both the doctors accused are innocent. There is no evidence whatsoever. [The investigation was run by] lousy and biased cops and the media was running berserk.”

Leif GW Persson, Telegraph

In 2005, police DNA tested the towel that had been found close to the second dumpsite. Hairs on the article were proven to have not come from either of the two doctors. In 2009, police officially suspended the investigation into the murder of Catrine da Costa with 25 years having passed since the crime was committed and the statute of limitations now being up.

With most now agreeing that Härm and Allgen were innocent, speculation as to who was truly responsible has focused on one man, Stanislaw Gonerka. In 1984, Gonerka had recently been released from a mental institution and his name was discovered in da Costa’s diary. He had been seen with prostitutes in Stockholm around the time of the killing with many saying they were fearful of him. Gonerka was a butcher, and in 1974 he had been sentenced to prison for the murder of a young woman. He strangled her before dismembering the body and discarding the remains in bin bags, the head was never found. Gonerka died in 1987.

While Stanislaw Gonerka seems a good fit for the murder of Catrine da Costa the case remains officially unsolved. It is likely to be little comfort to Härm, Allgen or the family of Catrine da Costa. The focus on the two suspects based on little evidence more than gossip, false witness, and public distaste for them personally likely allowed a brutal murderer to walk free. Fueled by the tabloid press and political pressure, the investigation and justice system lost all sense of impartiality and detachment, creating a witch-hunt like atmosphere that destroyed the lives and careers of two of Stockholm’s most promising medical professionals, leaving a family without true justice. To this day, claims exist online that Härm and Allgen were members of a Satanic cult, that they murdered many more women and that they engaged in cannibalism and even vampirism. Consistently denied compensation or to be allowed to work again, the case is one where there was no justice for anyone involved. It will remain one of the darkest and most shameful affairs in Swedish criminal history.

I am a freelance long-form writer who writes on true crime, politics, history and more. I am entirely self-funded and if you liked this article, please consider a donation via Patreon as a token of appreciation or directly via PayPal. You can join my mailing list for the latest articles and also like my Facebook page. I’m also active on Twitter. I can be contacted for projects through my website MichaelEastWriter.com where you’ll also find lots more content.

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Michael East

Written by

Freelance writer. Writing on true crime, mysteries, politics, history, and more. | https://linktr.ee/MichaelEast

The Mystery Box

A publication about unsolved mysteries from the deep ocean to space and from antiquity to present day.

Michael East

Written by

Freelance writer. Writing on true crime, mysteries, politics, history, and more. | https://linktr.ee/MichaelEast

The Mystery Box

A publication about unsolved mysteries from the deep ocean to space and from antiquity to present day.

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