Thijs H. killed three people in May 2019: a woman of 56 in The Hague on May 4, then a woman of 63 and a man of 68 in Heerlen, in South Limburg, on May 7. The three victims did not know one another, and all three were out walking when they died. The police alert that followed named a 27-year-old student from The Hague who had grown up near Heerlen. He was arrested late on the evening of May 8, a day after the second event.
The case has been argued in court for years, but the argument was never about who did it. He confessed in August 2019 and repeated the admission in court. What the courts had to decide was how far a mental disorder explained what he did. Experts at the Pieter Baan Centrum, the Dutch institute for forensic psychiatric observation, advised that he was in a psychosis and "volledig ontoerekeningsvatbaar", fully not criminally responsible. Had a court accepted that, he would have faced a hospital order and no prison term. The Rechtbank Limburg in 2020, the Gerechtshof 's-Hertogenbosch in 2022 and the Hoge Raad in 2023 each declined to do so. Each found him "verminderd toerekeningsvatbaar", of diminished criminal responsibility, and each upheld a conviction for murder. The sentence is a long prison term together with tbs met dwangverpleging, a hospital order with compulsory treatment.
The case also left questions about the mental health care he received in the months before. His parents asked for help in the days between the two events, and the clinic where he was a patient suspected him of the killings and did not tell the police. Those questions reached the Dutch parliament.
Little is known of his childhood. He grew up in or near Brunssum, a town in South Limburg, and lived with his parents there until shortly before the killings. NOS, the Dutch public broadcaster, reported in May 2019 that he had completed a first-year program at Zuyd University of Applied Sciences in South Limburg, then earned a bachelor's degree in cultural anthropology and development sociology at Leiden University. He was writing a master's thesis in industrial ecology at Delft University of Technology. In Leiden he had served a board year at a study association, where he handled book sales. For about a year he worked as a data analyst at an Amsterdam start-up while finishing two degrees, and a former employer told NOS that he turned down an offer to return because he wanted to graduate cum laude.
People who had known him gave NOS mixed impressions. A former housemate called him intelligent and kind, and also somber and withdrawn; she said he kept to his room. A former employer described him as driven, kind and quiet. Former fellow students said he was friendly but kept to the edges. DutchNews, in its own report of the same weeks, carried the same description of a social, intelligent but somber student.
About two weeks before the first killing he moved from his parents' home into a student house in The Hague. A neighbor in the building told NOS that he broke a bathroom door soon after arriving. The Public Prosecution Service confirmed within days of the arrest that he had earlier been treated at a mental health institution, and later reports place the start of that treatment in the autumn of 2018.
The institution was Mondriaan, a mental health provider with a clinic in Maastricht. NOS reported in March 2020, drawing on an inspectorate letter and a review commissioned by the institution, that he came under its care in the autumn of 2018. Caregivers did not identify a psychosis at the first contacts; the institution's own review found that the first assessment had been carried out adequately. Its independent committee questioned whether caregivers pressed him closely enough in later contacts to detect a psychosis, and the caregivers told the committee that he might have misled them.
Experts who testified at the 2020 trial gave a sharper account. A psychiatrist from the Pieter Baan Centrum told the court that he had not been adequately helped before the killings. The care, the court heard, had concentrated mainly on autism and ADHD, and the signs of a psychotic disorder had been pushed to the background. In the expert's words, the red flag "seems to have retreated into the background". A Mondriaan psychiatrist said psychotic symptoms had been noticed but read differently. On the institution's advice he had changed medication, and the Pieter Baan psychiatrist called the change unwise and said he should have been monitored more closely while it happened.
The inspectorate looked at the clinic after the killings. In a letter reported on March 9, 2020, it said that the decision to keep suspicions confidential rested with the caregiver and that no legal duty to inform the police existed. The independent committee reached the opposite view on that point and concluded that the clinic should have raised the alarm sooner. The parents did not cooperate with that review.
Etsuko was 56 and lived in The Hague. DutchNews described her as a woman of Japanese origin who often walked her two dogs. Her relatives, through their lawyer, told the 2020 trial that they doubted the finding that Thijs H. had acted in a psychosis.
The woman of 63 and the man of 68 killed in Heerlen both came from the Heerlen area. Police identified them on May 8, 2019 and released no names or initials at that stage. Little has been made public about either of them beyond their ages and the fact that they were out walking.
The families of the two Heerlen victims asked the municipality of Heerlen to cancel a silent march planned for the Friday after the second event, saying they were not yet ready for it. At the 2020 trial, relatives of the victims spoke to Thijs H. directly in the courtroom.
According to his own account at trial, Thijs H. had come to see messages in coded form in news reports and on vehicle license plates. They told him, he said, to kill two people, and his family would be killed if he did not. He believed he would be killed himself afterward.
On Saturday, May 4, 2019, in The Hague, he killed the first of the three, the woman of 56. He then returned to his parents' home in Brunssum. By his testimony, the message read in the signs on his way was that the first task had not been carried out properly and that two more people must die.
On Tuesday, May 7, in Heerlen, he killed the woman of 63 and, shortly afterward, the man of 68. He told the Maastricht court in June 2020 that he had earlier let another passerby go on that day. In his words, he had not gathered the courage; he said the young age of that person played a part. The appeal court later cited a young woman he let go as evidence of choice, not blind compulsion. He said that after the second event he read in the license plates that he had now done what was asked.
That same Tuesday, May 7, he went to the Mondriaan clinic in Maastricht. NOS reported in August 2019, after the investigation became public, that the clinic suspected he was involved in the killings but did not inform the police, citing medical confidentiality. He left the clinic that evening and his parents brought him back. Staff decided that he should move to a closed ward. During the night a separate violent incident involving another patient took place at the clinic, which the prosecution said had nothing to do with the investigation. On Wednesday, May 8, he left the clinic again in the confusion that followed. This time, NOS reported, the clinic no longer considered itself bound by confidentiality and contacted the authorities.
Until then the police had two inquiries that were not clearly linked: one in The Hague and one in Limburg. NOS reported that, after an appeal on the television program Opsporing Verzocht, police received dozens of tips in each case and examined camera footage near the places involved. The identification of Thijs H. came through the clinic. On the afternoon of May 8 police identified him and visited his parents in Brunssum. That evening they asked the public for help, released his photograph and warned people not to approach him because of a possibly unstable state of mind. The alert went out on a national wanted list. He was arrested at about 10:30 that night in South Limburg, DutchReview reported, without the exact place disclosed. NOS later gave the town as Margraten. NL Times placed the arrest on May 9, but the police announcements and NOS and DutchReview put it late on the evening of May 8.
Reports on May 9 said he had been admitted to a psychiatric institution and was held in full restriction. His lawyer expected him to appear before a judge the next day. The first hearing in the criminal case was a pro forma hearing at the Limburg court on August 16, 2019. There, NOS and NL Times reported, he confessed to all three killings. He said voices had given him orders during a psychosis, and at the close of the hearing he spoke to the families present: "Het spijt me verschrikkelijk wat er gebeurd is", which translates as "I am terribly sorry for what happened." He said he would cooperate fully with the observation at the Pieter Baan Centrum.
Before that, he had first said he had no memory of the events, and then that he remembered. The prosecutor told the court in August that the evidence included an abundance of DNA material and witnesses who placed him near the places concerned. His lawyer asked the court to be cautious in judging the police investigation, arguing that thoughts in his head had led him to lie while being questioned. The prosecution also said that, according to its inquiries, he had read online material about how to mislead judges before the killings, a claim that later became central to the dispute about the Pieter Baan report. He remained in custody. The observation at the Pieter Baan Centrum was to begin later that month.
The trial opened before the Rechtbank Limburg in Maastricht on June 22, 2020, with five hearing days scheduled. On the first day, NOS reported, Thijs H. described the delusions he said he had lived through. He told the court that a delusion had formed in his head, that he saw instructions in coded form in news reports and on vehicle license plates, and that he understood them to mean he had to kill two people. He believed his family would be killed if he did not, and that he would be killed himself afterward.
On the second day, June 23, relatives of the victims addressed the court directly. The relatives of the woman from The Hague, speaking through their lawyer, said they doubted that a psychosis explained what had happened.
The same day, experts from the Pieter Baan Centrum gave evidence. They maintained their advice that he be declared fully not criminally responsible and be given tbs met dwangverpleging. They told the court that his psychotic disorder had been overshadowed in his earlier care by attention to other conditions.
On June 30, 2020, the prosecution asked for 24 years in prison together with tbs met dwangverpleging. It treated all three counts as murder committed with premeditation, and it accepted diminished, not absent, criminal responsibility. Its argument was that full non-responsibility was not proven. It called the Pieter Baan conclusion doubtful, because the institute had not had the full file, and because the records of the mental health institution did not show that he had been psychotic. It said that he had contributed to any psychosis himself through substance use and through medication that had not been prescribed to him, despite warnings. It regarded the accounts that his family and friends had given the Pieter Baan experts as unreliable, and said the parents had helped shape the story and had interfered in the observation. The prosecutor said his mental condition was "verre van gezond", far from healthy, but attributed it in part to his own conduct, and said he had a very large interest in being declared fully not responsible. The prosecution cited reports that he had looked up online how to behave so that experts would think he had a serious disorder.
The prosecutor said the maximum sentence for triple murder would have been fitting, but asked for less because of the diminished responsibility, the brutality of the acts and the suffering of the relatives.
On July 1 his lawyers asked the court to follow the Pieter Baan advice and impose a hospital order with compulsory treatment and no prison term. They argued that he had been seriously mentally ill when he killed. They rejected the prosecution's criticism of the experts, saying that if even half of it were true the reporting experts would be unfit for their profession. They also objected to the prosecution's remarks about the parents, who they said had been torn down without a chance to reply.
In his last word, read from a note, Thijs H. expressed deep regret. "Dit had nooit mogen gebeuren en ik zou niets liever willen dan mijn daden ongedaan maken," he said: this should never have happened, and he would want nothing more than to undo what he had done. He said he was not a cruel person and that, in his belief at the time, he had no choice.
On July 30, 2020, the Rechtbank Limburg found the three murders proved. Its press release on the judgment (ECLI:NL:RBLIM:2020:5621) says that he committed them in a psychosis, having understood from messages that he had to kill or his family would be harmed. It also says that the Pieter Baan experts had advised declaring him "volledig ontoerekeningsvatbaar", on the information available when they wrote. After extensive consideration, partly on information that came to light after their study, the court "oordeelt ... de verdachte verminderd toerekeningsvatbaar": it held him to have diminished criminal responsibility. That finding allowed it to impose a prison term as well as tbs. It sentenced him to 18 years' imprisonment and tbs met dwangverpleging.
NOS, reporting the oral judgment, quoted the judges' reasoning. He had made deliberate choices: he went to places with "voldoende mensen maar niet te veel", enough people but not too many, and took steps to keep his phone from being traced. The crimes were not impulsive, and his claim that he had been ordered to commit them was rejected. "U heeft zelf bepaald wie u doodde, en wanneer", the court told him, in NOS's report: you decided yourself who you killed, and when. Before first speaking of delusions he had looked up the dangers of certain medications and borrowed a book about psychosis, and the court concluded that he had exaggerated his symptoms. DutchNews summarized the judgment as holding that his psychiatric problems were less serious than he had claimed. The court nonetheless accepted that he had a psychiatric disorder, and ordered treatment because of the high risk of reoffending that experts had identified. The presiding judge said he could not imagine the fear and pain the victims had felt, and that the killings had caused fear and unrest in society.
The court ordered him to pay the relatives who had filed claims a total of 103,498.08 euros: four claims were granted in full, one in part and one rejected. Both sides could appeal, and the case went to the appeal court, where the prosecution asked for a longer term.
The appeal went to the Gerechtshof 's-Hertogenbosch. On April 2, 2021, the court decided on the investigation requests before the hearing. Neither the defense nor the prosecution had asked for new research, but the court ordered a new examination by a psychologist and a psychiatrist, noting that the Pieter Baan report was over a year old and that the first-instance court had departed from the experts' advice. It also decided to hear the first-instance experts again, a psychiatrist who could explain the ADHD medication he had received, and the suspect's parents.
The new examination was carried out by researchers from the Netherlands Institute for Forensic Psychiatry and Psychology. In February 2022 NL Times, citing the regional broadcaster L1, reported their conclusion: a psychotic state could not be confirmed with complete certainty, and substance use might have caused the symptoms. That contradicted earlier experts, who had found psychosis present and substance use a symptom of it. Per the prosecution's later summary, the new rapporteurs said he did not have schizophrenia and that, if he had been psychotic, it resulted from substance use. They gave no view on criminal responsibility, and described him as impenetrable and dangerous. His lawyers, Serge Weening and Job Knoester, maintained that severe psychosis was the only explanation for the killings.
On February 15, 2022, the advocate-general asked the court for 30 years in prison and tbs. The prosecution said he had known exactly what he wanted before and during the killings, as his own statements showed, and treated premeditation as proven. The facts could justify life imprisonment, it said, but it chose a fixed term with tbs because treatment was needed to prevent reoffending, and releasing him untreated would be irresponsible.
The Gerechtshof ruled on March 17, 2022 (ECLI:NL:GHSHE:2022:868). It found three murders proved. Its press release says he acted deliberately and purposefully: he chose the victims, the time and the place himself, prepared for it, and tried not to be traced. He let a young woman go. The court concluded that this was no impulsive act, and that "niet in een gemoedsopwelling" was how he acted, "integendeel", quite the contrary.
On criminal responsibility, the court weighed three psychiatric reports. Two advised that he be declared fully not responsible. The third, commissioned by the court's investigating judge, gave no advice, because the experts had insufficient insight into his inner world. The court held that his conduct had been determined "tot op zekere hoogte", to a certain degree, by a disorder, but it did not follow the advice to declare him "volledig ontoerekeningsvatbaar". It declared him "verminderd toerekeningsvatbaar".
It imposed 22 years in prison and tbs met dwangverpleging. The maximum for murder is life or 30 years. It explained the higher sentence by saying the first court's term had not done enough justice to the seriousness of the acts, the number of victims, his responsibility despite his diminished state, the grief of the relatives and the unrest in society. It also granted most of the claims for damages, including loss of affection, funeral costs and a memorial place for one of the victims, again 103,498 euros in total.
The lawyer for the relatives, Sebas Diekstra, said that his clients could accept the sentence given the court's clear reasoning. The same afternoon, in consultation with his lawyers, Thijs H. decided to appeal to the Hoge Raad. At that point he was held at the penitentiary psychiatric center in Vught. His lawyers said the court had departed from the experts' advice without enough explanation, and that it had accepted a disorder without naming it while finding it affected his behavior only in part, where the experts who addressed the question had said it affected his conduct fully.
The Hoge Raad ruled on Tuesday, October 17, 2023. The procureur-generaal had advised that the conviction could stand, on the view that a person with a psychiatric disorder can still have thought about the meaning and consequences of a planned act.
The prison term was reduced from 22 years to 21 years and 10 months, as ANP reported in 2024; the finding of diminished responsibility and the tbs met dwangverpleging stood. A legal commentary in the Nederlands Juristenblad (2024), which cites the ruling as ECLI:NL:HR:2023:1295, treated it as setting out how a judge should assess a disorder when deciding on full non-responsibility under article 39 of the Criminal Code: the judge decides whether a disorder exists and is not bound by the advice of experts, a disorder in the legal sense is enough, and the judge need not name a specific diagnosis. The commentators questioned whether that gave the finding enough legal content.
The killings prompted a political debate about mental health care. On November 18, 2019, parties in the Dutch parliament called on the government to act after reports that his parents had unsuccessfully sought his admission just before the second event. A member of the PvdA said it could not be explained that the parents' cries for help had not been taken seriously. The SP asked for a debate with the State Secretary for Public Health, and the CDA said better exchange of information was needed. In March 2020 the institution's own review concluded that the clinic should have raised the alarm sooner, while the health inspectorate found no legal duty to inform the police and saw no need for sanctions.
The rapporteurs' report became the subject of a disciplinary case. On May 29, 2024, the Centraal Tuchtcollege voor de Gezondheidszorg in Den Bosch reprimanded the psychiatrist and the psychologist who had written the court-ordered report in the appeal. Thijs H. had filed the complaint, calling the report steering, biased and suggestive. The college found that the two had not answered whether he was psychotic before or during the crimes, though that was of great importance to the appeal court, and had not advised on criminal responsibility. It said they had not adequately justified why they thought he was not under the influence of a psychosis ("een sluitende onderbouwing ontbreekt"), that they had worked from partly redacted documents without asking for complete versions, and that the psychiatrist's wording had not been sufficiently neutral.
On August 25, 2026, ANP reported that an advocate-general had advised the Hoge Raad to reject Thijs H.'s request to reopen the case. The request followed the disciplinary ruling. The advice is not a decision, and no ruling on the request had been reported by then.
No court found him "volledig ontoerekeningsvatbaar" (fully not criminally responsible). No court acquitted him, and none ordered "ontslag van alle rechtsvervolging" (discharge from prosecution). The Rechtbank Limburg (2020), the Gerechtshof 's-Hertogenbosch (2022) and the Hoge Raad (2023) each upheld a conviction for three murders (moord) with a finding of "verminderd toerekeningsvatbaar" (diminished criminal responsibility). The sentence combines a prison term with tbs met dwangverpleging. The Pieter Baan Centrum alone advised full non-responsibility, and two of the three reports before the appeal court did the same.
Whether he was psychotic is the central dispute. The Pieter Baan experts and the two reports before the appeal court that advised full non-responsibility said yes. The prosecution doubted it, citing the institution's records and his internet searches. The court-ordered report in 2022 could not confirm it. The courts did not decide that he was not psychotic; they held that, whatever his condition, he had made deliberate choices, and that the disorder explained his conduct only in part. The disciplinary college later found the 2022 report's reasoning on this point inadequate.
The prosecution also raised, at the August 2019 hearing and in 2020, whether his parents had influenced the experts' observation and the story told to them. The defense called that unfair to the parents. That allegation is the prosecution's position, not a finding.
Accounts differ slightly on dates and ages. The Heerlen woman is 63 in the court records and 64 in one NL Times report. The arrest is dated late on May 8, 2019 by the police announcement, NOS and DutchReview, and May 9 by NL Times.
Autumn 2018: begins treatment at the Mondriaan institution.
About two weeks before May 4, 2019: moves from his parents' home in Brunssum to a student house in The Hague.
May 4, 2019: a woman of 56 is killed in The Hague.
May 7, 2019: a woman of 63 and a man of 68 are killed in Heerlen; that day he goes to the Mondriaan clinic in Maastricht, leaves, and is returned by his parents.
May 8, 2019: leaves the clinic again; police identify him and appeal to the public; he is arrested late that evening in South Limburg.
August 16, 2019: confesses at a pro forma hearing in Maastricht.
November 18, 2019: parties in parliament call for action on mental health care.
March 9, 2020: inspectorate letter and independent review of the institution are reported.
June 22, 2020: trial opens in Maastricht.
June 30, 2020: prosecution asks for 24 years and tbs.
July 30, 2020: Rechtbank Limburg convicts him of three murders as "verminderd toerekeningsvatbaar"; 18 years and tbs met dwangverpleging.
April 2, 2021: appeal court orders a new psychological and psychiatric examination.
February 15, 2022: prosecution asks the appeal court for 30 years and tbs.
March 17, 2022: Gerechtshof 's-Hertogenbosch sets 22 years and tbs; he appeals to the Hoge Raad.
October 17, 2023: Hoge Raad rules in the cassation appeal; term reduced to 21 years and 10 months.
May 29, 2024: disciplinary college reprimands the psychiatrist and psychologist who wrote the appeal report.
August 25, 2026: advocate-general advises the Hoge Raad to reject his request to reopen the case.