The High Court at Kibera has found a former estate caretaker guilty of the horrific double murder of his girlfriend and their three-month-old infant child, bringing a definitive end to an eight-year-old legal battle.
Delivering the judgment virtually, High Court Judge Dr. Kavedza convicted William Masika Tasika on two counts of murder, ruling that the prosecution had overwhelmingly proved its case beyond any reasonable doubt.
The prosecution detailed a chilling sequence of events that unfolded on the rainy evening of April 5, 2018, at a gated commercial compound along Ole Dume Road in Nairobi’s upscale Muthangari area. Maureen Emali, a tenant operating a reflexology clinic on the premises, testified to hearing the agonizing, intermittent screams of a woman in distress piercing through the heavy rainfall. Moments later, she observed Tasika emerging from the landlady’s upper-floor office, descending the stairs while leaving a trail of bloody footprints behind him. When confronted, Tasika deceptively claimed he had been ambushed by unknown individuals linked to a person named “Mercy” and fled the compound on a bicycle.
Upon entering the office shortly thereafter, estate directors and emergency responders were met with a scene of absolute carnage. Mercy Andeso was found lying near the entrance in a massive pool of blood, suffering from catastrophic, deep lacerations to her neck, chest, and ribs. In the adjacent bathroom, paramedics discovered their three-month-old daughter, unresponsive near a sink. A blood-soaked office knife and a heavy hammer were recovered next to the victims. Medical examinations later performed by pathologist Dr. Sylvester Maingi revealed that while Andeso bled to death from multiple sharp-force stabs, the defenseless infant had been brutally smothered to death, bearing visible bruising around her mouth and cheeks.
The court heard that late that evening, Tasika contacted his employer requesting money for medical treatment. Acting on a concealed police trap, arrangements were made for him to return. Sensing danger upon his arrival, Tasika attempted to sprint away from the main gate, diving into a nearby river ditch before being chased down and wrestled to the ground by officers.
At the time of his arrest, he was partially unclothed and had visible injuries. Investigative officer PC Vincent Siro later confirmed that comprehensive call data record analysis was used to eliminate initial suspects, firmly placing Tasika as the last person seen with the deceased.
In his defense, Tasika tried to argue a case of self-defense. He admitted that Andeso had brought the child to his quarters, where an argument erupted stemming from a long history of domestic disputes. He alleged that Andeso suddenly attacked him with a knife, and that her fatal injuries occurred entirely during a desperate, spontaneous struggle to protect his own life.
However, Justice Kavedza thoroughly dismantled the convict’s line of defense, noting that the nature, multiplicity, and severity of the injuries sustained by the adult deceased were completely inconsistent with a defensive or proportionate response. The court further pointed out that the death of the infant by suffocation was wholly incompatible with a sudden, spontaneous struggle, as the accused offered no explanation as to how a vulnerable three-month-old child came to be smothered. The judge ruled that Tasika’s immediate flight from the scene, his failure to render medical assistance to his family, and his frantic attempt to evade arrest heavily indicated a guilty mind.
The targeted use of an office knife against vital bodily organs established clear malice aforethought.












