The Dutch businessman disappeared in July 2019. Two months later, his body was discovered hidden in a septic tank at his Nairobi home. Allegations of domestic violence, a friend’s account of Cohen’s fears, a missing-person investigation and disturbing testimony from former household staff have shaped one of Kenya’s most closely watched murder cases.
Murder is one of the most serious crimes a person can commit. It destroys a life, devastates a family and leaves questions that can haunt loved ones for years. In jurisdictions where life imprisonment is available, the punishment reflects society’s determination that those responsible for unlawfully taking human life must face the gravest consequences.
The killing of Dutch businessman Tob Cohen shocked Kenya not only because of the circumstances surrounding his death, but also because of where his body was eventually found: concealed in a septic tank at the home he shared with his wife, Sarah Wairimu Kamotho Cohen.
Cohen disappeared in July 2019. His body was discovered in September that year after an investigation that exposed a deeply troubled marriage, conflicting explanations about his whereabouts and a series of developments that investigators were compelled to examine.
Wairimu was arrested and charged with his murder. She has denied the charge, but the prosecution’s case has drawn attention to testimony concerning Cohen’s final days, his reported fears, the couple’s disputes and the concealment of his remains.
The case raises a fundamental question about accountability: if the evidence establishes that Wairimu deliberately killed her husband, what punishment would adequately reflect the seriousness of the crime?
For those seeking justice for Cohen, life imprisonment is a compelling demand.
A marriage under strain
Tob Cohen was a Dutch national who had lived in Kenya for decades. He was associated with the country’s golf tourism industry and built a professional life that connected him to businesspeople, golfers and other members of the community.
He married Wairimu in 2007. Over time, their relationship became troubled, with disputes that eventually attracted police attention.
In February 2019, Cohen reportedly made a complaint to the police alleging that his wife had assaulted him. The complaint became part of the background investigators examined after his disappearance. Police officers subsequently testified about their involvement in the matter and the difficulties surrounding efforts to pursue it.
The earlier complaint was significant because it indicated that the couple’s domestic conflict had extended beyond private disagreements. It also provided investigators with a timeline against which later events could be examined.
The marriage reportedly involved disagreements over property, money and other personal matters. Witnesses would later describe Cohen as fearful and concerned about his circumstances in the months and days before his death.
Such disputes do not, by themselves, establish responsibility for murder. But in reconstructing a suspicious death, investigators must examine the relationship between the deceased and those closest to him, including any documented conflict, threats or conduct that might help explain what happened.
In Cohen’s case, those questions became inseparable from the search for answers about his disappearance.
The final warning that haunts the case
One of the most striking moments in the trial came in October 2026, when Patrick Kariuki Muiruri, Cohen’s close friend and a former Gatundu MP, testified about a telephone conversation he said he had with the businessman on the night of July 19, 2019.
Muiruri told the High Court that Cohen was deeply troubled by the escalating conflict in his marriage and feared for his safety. He recounted that his friend had complained about police officers failing to arrest Wairimu over the earlier assault complaint.
According to Muiruri, Cohen was explicit about whom he feared.
“If anything bad happens to me, if I’m found dead somewhere, tell them it’s Sarah behind it,” he recalled Cohen saying.
The witness said the conversation lasted approximately 15 to 20 minutes and was their last.
The testimony presents a troubling account of Cohen’s state of mind shortly before he disappeared. His friend also told the court that Cohen had discussed plans to divorce Wairimu and had complained about disputes involving property documents and money associated with their business.
For prosecutors, the testimony forms part of the wider picture they are presenting about the relationship and the circumstances preceding Cohen’s death.
The significance of the warning is difficult to overlook. A man who reportedly expressed fear about his safety subsequently disappeared, and his body was eventually found concealed at his residence. The prosecution must connect those circumstances to the evidence establishing who killed him.
The Thailand story and the concrete covering
When Cohen’s employees returned to the residence after the weekend, he was nowhere to be found. Former employee Mathew Muiruri Kinyanjui testified that Wairimu told staff to say Cohen had travelled to Thailand for medical treatment.
Kinyanjui said he initially repeated that explanation to police but later returned to investigators to give a different account. He also told the court that he noticed freshly poured concrete covering the septic tank and two other areas at the compound.
These details became central to the investigation because they raised questions about whether the explanation for Cohen’s absence was consistent with what investigators subsequently discovered.
In September 2019, detectives recovered Cohen’s body from the underground tank. Forensic personnel documented the operation, collecting exhibits and recording the scene.
The discovery was horrifying in its implications. A missing businessman had been found dead and concealed within the property where he lived. The circumstances demanded an investigation capable of establishing how he died and whether anyone had deliberately attempted to hide the crime.
Investigators examined the residence, vehicles, bedrooms and other areas, while forensic witnesses later testified about the exhibits recovered and the results of laboratory examinations.
The prosecution has relied on this evidence alongside witness accounts to build its case against Wairimu. The defence has challenged aspects of the investigation and the testimony, making the court’s examination of the evidence particularly important.
A trial marked by delays and fresh charges
Wairimu was initially charged after Cohen’s body was discovered in 2019. The proceedings subsequently took a complicated route. In December 2022, the prosecution withdrew the existing murder charges against Wairimu and businessman Peter Karanja, paving the way for an inquest.
The murder case was later revived, and Wairimu was arrested again after prosecutors reviewed the file and decided to pursue a fresh charge. She has pleaded not guilty.
The renewed proceedings have brought police officers, former household workers and other witnesses before the High Court in Kibera. Their testimony has covered the alleged assault months before Cohen’s death, the final known movements of the businessman, the circumstances of his disappearance and the recovery of his body.
The trial has also exposed the difficulties of investigating a crime in which much of the relevant evidence concerns events inside a private home. Investigators must reconstruct the sequence of events through witness testimony, records, forensic findings and the physical circumstances surrounding the discovery.
For Cohen’s relatives, the proceedings represent a long wait for answers. For the prosecution, they provide an opportunity to establish its allegations in court. And for the accused, the trial is where the evidence against her must be examined.
Why life imprisonment should be on the table
The case against Wairimu carries a disturbing combination of alleged domestic violence, reported fear for personal safety, a sudden disappearance, an explanation that employees were instructed to repeat, and the eventual discovery of a body concealed in a septic tank.
Taken together, these are serious matters that demand a full accounting.
If the prosecution establishes that Wairimu deliberately killed Cohen and that the concealment of his body formed part of the crime, the appropriate punishment should reflect the gravity of those acts. Life imprisonment should be firmly considered in light of the circumstances established in court and the applicable sentencing law.
A human life cannot be restored through a court judgment. But punishment serves an important purpose: it holds offenders accountable and affirms that the deliberate taking of another person’s life carries consequences.
Cohen was 71 when he died. He had built a life and career in Kenya, cultivated friendships and maintained business interests. His death left his family with grief and a prolonged search for answers about what happened during his final hours.
The allegations surrounding his killing also raise wider concerns about domestic violence and the ability of people who report threats or assaults to obtain effective protection. His earlier police complaint is a particularly troubling part of the chronology because it preceded his disappearance by only months.
The court must determine what the evidence establishes about Wairimu’s responsibility. But the public interest in a clear answer is unmistakable.
If she is found guilty of murdering her husband, a substantial sentence, including life imprisonment where justified by law, would reflect the seriousness of the offence and the harm caused. A crime of this magnitude should not be treated lightly.
Justice for Tob Cohen
Nearly seven years after Cohen disappeared, the case remains a grim reminder of how a missing-person investigation can uncover a far more disturbing reality.
The reported warning to his friend, the account given to household employees, the concrete covering the septic tank and the eventual recovery of his body have become defining elements of a case that continues to attract public attention.
The prosecution is seeking to establish how these events fit together and who was responsible for Cohen’s death. Wairimu’s trial remains the forum in which that case is being tested.
For those who believe she should face life imprisonment, the demand is straightforward: if the evidence proves that she murdered her husband, the punishment should match the severity of the crime.
Tob Cohen deserves justice. If Sarah Wairimu is convicted of his murder, life behind bars should be among the strongest sentencing options considered by the court.
