The Murder of Monica Kimani

Monica Kimani and the 2018 investigation

Monica Kimani was a Kenyan businesswoman whose body was found at her apartment in Kilimani, Nairobi, on September 20, 2018. The High Court record states that the prosecution alleged she had been murdered during the previous night. Medical evidence presented at trial attributed her death to severe neck injuries caused by sharp force.

The investigation eventually led prosecutors to charge Joseph Kuria Irungu and Jacqueline Wanjiru Maribe jointly with murder. Both pleaded not guilty. The case then moved through a lengthy High Court trial in Nairobi, where the prosecution relied heavily on circumstantial evidence rather than an eyewitness account of the killing itself.

The evidence considered by the High Court

In its February 9, 2024 judgment, the High Court reviewed evidence about Irungu's movements, access to Monica's apartment complex, clothing, identification used at the premises, communications and events after he left the area. The court also considered forensic and medical evidence, witness testimony and the explanations offered by both accused persons.

The judgment found the chain of circumstantial evidence against Irungu sufficient to prove murder beyond reasonable doubt. The same court did not find evidence sufficient to prove that Maribe participated in Monica's murder. She was therefore acquitted of that charge.

The February 2024 verdict

On February 9, 2024, Justice Grace Nzioka convicted Joseph Kuria Irungu of Monica Kimani's murder. The court rejected his denial that he knew Monica and concluded that the prosecution's circumstantial case placed him at the center of the killing.

Jacqueline Maribe was acquitted of murder. The judgment discussed false information she had given investigators, but because she had not been charged with a separate false-information offence, the court did not substitute a different conviction for the murder charge.

The sentence

On March 13, 2024, the High Court sentenced Irungu to death under Kenya's murder statute. The sentencing decision recorded aggravating and mitigating submissions, the effect of the crime on Monica's family, the fact that Irungu was a first offender, and Kenyan precedent recognizing judicial discretion in murder sentencing after the Supreme Court's Muruatetu decisions.

The sentencing judgment did not erase Irungu's right to challenge the conviction and punishment through the appellate process. Two days later, reporting confirmed that his legal team had filed notice of appeal against both conviction and sentence.

Appeal and constitutional challenge

The post-trial proceedings have moved slowly. Reporting in 2025 described delays in preparation and service of the criminal appeal record. By 2026, Irungu was also pursuing a separate High Court petition challenging legal restrictions affecting death-row prisoners and the constitutionality of the death sentence imposed on him.

A July 31, 2026 report described Monica Kimani's family seeking participation in the constitutional case over the death penalty. The conviction itself had not been reported as overturned. For that reason, this archive treats the murder as adjudicated while keeping the appellate posture visible rather than describing the case as legally finished.

What remains unresolved

The criminal court reached a conclusion on Irungu's responsibility, but several questions remain outside that finding. Public reporting has not established a definitive motive accepted by the court, and the continuing appeal means the conviction and sentence remain subject to review. Crime by Region does not fill those gaps with speculation.

The distinction is important: adjudicated responsibility is not the same thing as exhausted appeals. The current classification records what the trial court decided while acknowledging that higher-court proceedings can still change the legal outcome.

Timeline

Current status

The case is Solved / Adjudicated, with appellate and sentence-related proceedings continuing. Joseph Kuria Irungu remains convicted of Monica Kimani's murder under the High Court judgment of February 9, 2024 and was sentenced to death on March 13, 2024. Jacqueline Wanjiru Maribe was acquitted of murder.

Related country archives