How technology is helping crack Kenya’s toughest murder cases

This story has significance for readers across Kenya and beyond.

When prosecutors opened the murder trial over the death of teacher and blogger Albert Ojwang last month, one witness stood out from the rest: the silent eye of a surveillance camera.

For hours, CCTV footage captured inside Nairobi’s Central Police Station was played on courtroom screens as prosecutors painstakingly reconstructed Ojwang’s final hours.

The recordings showed the movements of former OCS Samson Tallam, police officers James Mukhwana and Peter Kimani, former GSU Unit officer John Ngige Gitau, Gin Ammitou Abwao and Brian Mwaniki Njue, placing them at critical locations before Ojwang was found dead.

This footage has become the backbone of the prosecution’s case. Whether it is sufficient to secure convictions will ultimately be determined by the court.

The Ojwang trial shows a broader shift in Kenya’s criminal justice system, where investigators are increasingly relying on digital evidence to solve complex murders that would previously have depended almost entirely on eyewitness testimony or confessions.

As the investigation into the murder of Dr Victoria Mutiso continues, detectives are pursuing several lines of inquiry and are not treating the July 29 shooting as an isolated attack.

They are following various leads, including the forensic analysis of CCTV footage and call data records. So far, at least eight suspects have been named, including three police officers.

CCTV footage, mobile phone data, DNA analysis, geospatial mapping, M-Pesa transactions, digital photographs and forensic examination of electronic devices have all become indispensable investigative tools today. These tools allow detectives to reconstruct crime scenes, establish timelines, trace suspects’ movements and corroborate witness testimony with remarkable precision.

Unlike eyewitnesses, electronic evidence is reliable. When analysed properly, it can verify or contradict witness accounts and expose suspects’ inconsistencies.

Technology has also reduced reliance on confessions, which are often challenged in court.

Technology has transformed homicide investigations, as demonstrated by several high-profile murder cases.

Sharon Otieno murder trial

The conviction of former Migori Governor Okoth Obado, his former PA Michael Oyamo, and former county officer Caspal Obiero shows how digital evidence can boost a circumstantial murder case. While no witness saw Sharon Otieno being killed, the prosecution relied on a combination of mobile phone evidence, digital records and vehicle tracking data to corroborate the testimony of 42 witnesses and reconstruct the conspiracy that led to her death.

One of Justice Cecilia Githua’s key findings was that Oyamo had deliberately acquired an Airtel line, using a stolen identity card, shortly before the murder. The court found that this phone line was intended to conceal his identity when communicating with Sharon and the others involved in executing the plan.

The prosecution presented M-Pesa records showing how money flowed from Obado to Sharon while he was trying to persuade her not to reveal their relationship or her pregnancy.

Investigators also established that Sharon and the journalist with her were instructed by their abductors to switch off their mobile phones just before they were driven away, preventing any subsequent tracking.

The court also heard that the vehicle used had its tracking device disabled on the day of Sharon’s abduction.

Justice Githua said disabling the tracking system was evidence of planning and an attempt to conceal the movements of those involved in the crime.

She concluded that Obado had financed the plot, Oyamo coordinated its execution, and Obiero helped to cover it up after the killing. DNA tests on the foetus confirmed Obado was the biological father of the unborn baby.

The court held that the digital evidence, alongside witness testimony and other circumstantial evidence, formed an unbroken chain pointing irresistibly to the guilt of the three accused.

Rex Masai case

The inquest into the death of Rex Kanyike Masai, will also heavily rely on CCTV footage, forensic video analysis and mobile phone triangulation to reconstruct the events leading to his shooting.

So important is the digital evidence that NPS persuaded the court to allow fresh testimony from witnesses who had already testified, despite opposition from the IPOA, which had already closed its case. Rex was shot during the anti-Finance Bill protests on June 20, 2024.

NPS was allowed to recall representatives from the Integrated Command, Control and Communication Centre (IC3), Absa Bank, International Life House and Bliss Hospital, whose evidence is expected to shed light on CCTV footage and the sequence of events on the day of the protests.

It also permitted the NPS to call officers from Kamukunji, Kilimani, Parliament and Kenyatta International Convention Centre police stations to produce arms movement registers for June 20, 2024, documents that investigators believe could help identify the firearm and officer involved.

IPOA's lead investigator, Justin Nyatete, had told the court that the investigation faced attempts to frustrate the probe, including misleading information from key police officers, missing deployment records and alleged interference with the arms movement register at Central Police Station.

Nyatete said forensic video analysis of CCTV footage and photographs identified an armed undercover officer in civilian clothing at Moi Avenue and Mama Ngina Street. They said the officer's facial features, distinctive birthmark, clothing and accessories matched those of Police Constable Isaiah Murangiri Ndumba.

The digital trail extended beyond video evidence. IPOA said it obtained Murangiri's registered mobile phone numbers from Safaricom after he allegedly provided investigators with a number belonging to another person.

Phone records, metadata and cell-site triangulation were then used to place his handset in the CBD and near the protest route around the time Rex was shot.

Although Murangiri has denied being the officer captured in the footage and maintains he was not at the scene, the inquest is expected to test whether CCTV evidence, forensic image analysis and mobile phone location data, considered alongside witness testimony and official police records, can establish an accurate timeline and identify those responsible for Rex Masai's death.

KDF officer sentenced to life for murder

Technology also proved decisive in solving the murder case involving former Kenya Air Force Major Peter Mwaura Mugure, who was recently sentenced to life imprisonment for murdering Joyce Syombua and their two children. Investigators relied on an array of digital evidence to expose what the High Court described as a carefully planned murder.

M-Pesa records showed Mugure had sent Joyce money to facilitate her journey from Nairobi to Nanyuki with the children days before they disappeared. Mobile phone records later placed Joyce and the children inside the military base after they arrived.

Experts extracted data from mobile phones belonging to the victims and witnesses, helping investigators reconstruct their movements before the killings.

Messages deleted from Mugure’s phone, a recovered SIM card and digital records all corroborated witness testimony. DNA analysis confirmed the children’s paternity, providing prosecutors with a compelling motive for the murders. Justice Martin Muya concluded that the combination of witness testimony, digital evidence and forensic analysis proved the murders had been meticulously planned.

MP George Muchai’s case

Technology has also featured prominently in the prosecution of suspects linked to the killing of former Kabete MP George Muchai, his two bodyguards and driver in 2015.

While the suspects were convicted primarily of robbery with violence and sentenced to death, investigators relied on extensive forensic analysis and electronic evidence to piece together the movements of the gang responsible for a series of robberies and abductions that culminated in the fatal attack. The case arising from the killings is pending before the High Court.

Monica Kimani murder

Technology was key in prosecuting Joseph Irungu, alias Jowie, who was convicted of murdering businesswoman Monica Kimani. Investigators first reconstructed Kimani's final journey using airport surveillance systems. Passenger records established that she travelled from Juba aboard a Kenya Airways flight on September 19, 2018.

CCTV footage from JKIA tracked her movements from the aircraft to immigration, the baggage hall and finally to the taxi rank, where she boarded a cab to her apartment in Nairobi.

A Safaricom data analyst produced evidence showing that Irungu had communicated with Ms Kimani weeks before her death, contradicting his claim that he did not know her. The court viewed a video recovered from Irungu’s mobile phone showing him inside Kimani’s house before her murder.

Justice Grace Nzioka rejected Irungu’s denial that he knew the deceased, finding that the telephone records and digital evidence demonstrated the two had been in contact before the killing.

Lawyer Willie Kimani murder

Another striking case is the murder trial of lawyer Willie Kimani, his client Josephat Mwenda and taxi driver Joseph Muiruri.

They disappeared after leaving Mavoko Law Courts on June 23, 2016. Their bodies were later recovered from a river near Donyo Sabuk after being killed.

The prosecution relied on an extensive trail of digital evidence.

Justice Jessie Lesiit, who heard the case, considered more than 6,100 pages of documents, 117 exhibits and evidence from 80 witnesses before passing out the judgment. Among the most compelling exhibits were CCTV recordings and car tracking data.

The footage showed Kimani being picked up by taxi driver Muiruri in Westlands before travelling to Mavoko Law Courts, where he was representing Mwenda in a criminal case. After the court session, investigators say the trio was abducted and taken to Syokimau Police Post. Police communication records also traced the movement of radio equipment used by officers implicated in the killings.

Data placed the devices at several locations, including Mlolongo Police Station, Syokimau Police Post, Mombasa Road, Eastern Bypass and, crucially, near the site where the victims were murdered and their bodies stashed.

Former AP officer Fredrick Leliman was sentenced to death. His former colleagues Stephen Cheburet and Sylvia Wanjiku were sentenced to 30 and 24 years in prison, respectively. A police informer was jailed for 20 years.

Reporting originally appeared via Nation Africa. Read the full source for additional context.