1. The appellant, Yonah Waswa Mutambo, was charged with the offence of defilement contrary to section 8(1) as read with section 8(3) of the Sexual Offences Act. The particulars were that on diverse dates between 01st April 2024 and 27th May 2024 at Riamanoti Village in Borabu Sub-County within Nyamira County, he intentionally caused his penis to penetrate the vagina of S.B.M, a child aged fifteen (15) years. In the alternative, he faced a charge of committing an indecent act with a child contrary to section 11(1) of the Sexual Offences Act. The appellant denied both the main and alternative charges and the matter proceeded to a full trial.
2. At the conclusion of the trial, the learned trial magistrate found that the prosecution had proved the main charge beyond reasonable doubt, convicted the appellant of the offence of defilement and, on 12th June 2025, sentenced him to serve fifteen (15) years' imprisonment.
3. Dissatisfied with both the conviction and the sentence, the appellant lodged the present appeal challenging the findings of the trial court.
4. In his petition of appeal, the appellant faults the learned trial magistrate on several grounds, namely that the conviction was founded on insufficient and unreliable evidence; that the investigations undertaken by the prosecution were inadequate; that the complainant's mother, whom he considers to have been a crucial witness, was not called to testify; that despite his request no DNA analysis was conducted notwithstanding that the complainant became pregnant; and that the sentence imposed was manifestly harsh in the circumstances.
5. In his written submissions dated 04th May 2026, the appellant elaborates those complaints by contending that the prosecution withheld material witnesses whose evidence would have shed light on the issues in controversy, particularly the complainant's mother. He further argues that the investigating officer failed to recover or produce material exhibits, including the undergarments allegedly left at the scene, and generally conducted superficial investigations. It was also his contention that the failure to subject the child born to the complainant to DNA testing left unresolved the question of paternity and thereby rendered the conviction unsafe. On those premises, he urges this court to quash the conviction, set aside the sentence and allow the appeal.
6. This being a first appeal, the court is required to independently reappraise the entire record and reach its own determination, bearing in mind that it did not have the advantage of seeing or hearing the witnesses testify. The Court of Appeal in Imanyara & 2 others v Attorney General [2016] KECA 557 (KLR) restated that a first appellate court must evaluate the evidence afresh and arrive at its own conclusions, making due allowance for that disadvantage.
7. Having carefully considered the petition of appeal, the record of the proceedings before the trial court, the judgment appealed against and the appellant's written submissions, the following issues arise for determination:
1) Whether the prosecution proved the offence of defilement against the appellant beyond reasonable doubt.
2) Whether the alleged failure to call the complainant's mother, conduct DNA analysis and recover or produce certain exhibits rendered the conviction unsafe.
3) Whether there is any basis for interfering with the sentence imposed by the trial court.
8. The Court of Appeal in Olenkom v Republic [2026] KECA 798 (KLR) reaffirmed that to sustain a conviction for the offence of defilement under section 8 of the Sexual Offences Act, the prosecution must prove beyond reasonable doubt three essential ingredients, namely the age of the complainant, penetration and the identity of the perpetrator. The Court further observed that proof of age is indispensable because it determines both criminal liability and the applicable sentence; that age may be established by a birth certificate, an age assessment report, medical evidence or any other credible and reliable evidence; and that penetration may be proved by the complainant's testimony, with medical evidence serving a corroborative, rather than indispensable, role.
9. The first ingredient is the age of the complainant. The complainant (PW1) testified that she was born on 10th June 2008, and her testimony was corroborated by the birth certificate produced in evidence without objection. The charge alleged that the offence was committed between 01st April 2024 and 27th May 2024, during which period the complainant was fifteen (15) years old. I therefore find that the prosecution proved beyond reasonable doubt that the complainant was a child aged fifteen years at the material time, thereby bringing the offence within the ambit of section 8(3) of the Sexual Offences Act.
10. The second ingredient is proof of penetration. Section 2 of the Sexual Offences Act defines penetration as the partial or complete insertion of the genital organs of one person into the genital organs of another. The complainant testified that after the appellant professed his love for her, she accompanied him to his house where he removed his clothes, she removed hers, and inserted his penis into her vagina, causing her pain. She further testified that they engaged in sexual intercourse on another occasion before they were discovered together on the night of 27th May 2024. Her testimony was corroborated by the medical evidence, which disclosed findings consistent with penetration. In addition, the evidence showed that the complainant subsequently conceived and gave birth, a circumstance that lends further support to her account that she had engaged in sexual intercourse. I find the complainant's account to have been coherent, consistent and materially corroborated by the medical evidence. Consequently, I am satisfied that the prosecution proved the element of penetration beyond reasonable doubt.
11. The final ingredient is whether it was the appellant who perpetrated the offence. The complainant testified that she had known the appellant for about one and a half years before the commission of the offence, as he worked at the home of one Ombego. This was therefore a case of recognition rather than the identification of a stranger. She further testified that the appellant professed his love for her and that they engaged in sexual intercourse on more than one occasion over a period of time before arranging to meet again on the night of 27th May 2024.
12. PW2 stated that she saw the complainant and the appellant together that evening and alerted the complainant's mother. PW2 thereafter accompanied other members of the public to the appellant's residence, where the complainant was found hiding in a goat shed within the appellant's compound while the appellant was discovered concealed in a dog kennel. Those circumstances were wholly consistent with the complainant's account and significantly reinforced the prosecution's case on identity. The appellant's sworn denial did not displace that evidence or raise any reasonable doubt. I am therefore satisfied that the prosecution proved beyond reasonable doubt that it was the appellant who defiled the complainant.
13. The appellant also complained that the prosecution failed to call the complainant's mother as a witness, conduct DNA analysis and recover certain exhibits from the scene. With regard to the failure to call the complainant's mother, section 143 of the Evidence Act provides that no particular number of witnesses shall, in the absence of any provision of law to the contrary, be required for the proof of any fact. In Mutunga v Republic [2006] KECA 79 (KLR), the Court of Appeal reiterated that the prosecution has the discretion to determine the witnesses necessary to prove its case, and an appellate court will not interfere with that discretion unless it is shown to have been exercised improperly. In the present case, the complainant's mother was not an eyewitness to the acts of defilement, and the evidence of the complainant, PW2 and the medical evidence sufficiently established the charge.
14. Regarding the absence of DNA analysis, section 36(1) of the Sexual Offences Act empowers the court to direct the taking of samples for forensic analysis but does not make DNA testing mandatory. In Williamson Sowa Mbwanga v Republic [2016] KECA 147 (KLR) ,the Court of Appeal held that failure to conduct DNA analysis is not fatal where the prosecution has otherwise proved the essential ingredients of the offence beyond reasonable doubt.
15. Similarly, the failure to recover the alleged exhibits from the scene did not weaken the prosecution's case, as the offence was established by credible oral and medical evidence. I therefore find that none of the matters raised by the appellant created any reasonable doubt as to his guilt.
16. The appellant has also challenged the sentence imposed by the trial court. An appellate court will not ordinarily interfere with the exercise of sentencing discretion unless it is shown that the trial court acted on a wrong principle, overlooked a material factor, considered an irrelevant factor, or that the sentence imposed is manifestly excessive or manifestly inadequate in the circumstances. Where the sentence is lawful and the discretion has been properly exercised, an appellate court has no basis for interference.
17. The appellant was convicted under section 8(1) as read with section 8(3) of the Sexual Offences Act, which prescribes a sentence of not less than twenty years' imprisonment where the child is between the ages of twelve and fifteen years. The record, however, shows that the learned trial magistrate imposed a sentence of fifteen (15) years' imprisonment, which is below the statutory minimum prescribed by law.
18. The appellant alone appealed against both conviction and sentence, and the respondent neither filed a cross-appeal nor gave notice seeking enhancement of sentence. In those circumstances, while the sentence imposed was more lenient than that contemplated by section 8(3) of the Act, there is no basis upon which this court can enhance it in the absence of a cross-appeal or a notice for enhancement. Accordingly, I decline to interfere with the sentence imposed by the trial court.
19. Having independently re-evaluated the entire evidence on record, I am satisfied that the prosecution proved the offence of defilement against the appellant beyond reasonable doubt. The grounds of appeal are devoid of merit. I therefore find no basis for interfering with either the conviction or the sentence imposed by the trial court.
20. Accordingly, the appeal is dismissed in its entirety. The conviction for the offence of defilement contrary to section 8(1) as read with section 8(3) of the Sexual Offences Act and the sentence of fifteen (15) years' imprisonment are hereby affirmed.
2. At the conclusion of the trial, the learned trial magistrate found that the prosecution had proved the main charge beyond reasonable doubt, convicted the appellant of the offence of defilement and, on 12th June 2025, sentenced him to serve fifteen (15) years' imprisonment.
3. Dissatisfied with both the conviction and the sentence, the appellant lodged the present appeal challenging the findings of the trial court.
4. In his petition of appeal, the appellant faults the learned trial magistrate on several grounds, namely that the conviction was founded on insufficient and unreliable evidence; that the investigations undertaken by the prosecution were inadequate; that the complainant's mother, whom he considers to have been a crucial witness, was not called to testify; that despite his request no DNA analysis was conducted notwithstanding that the complainant became pregnant; and that the sentence imposed was manifestly harsh in the circumstances.
5. In his written submissions dated 04th May 2026, the appellant elaborates those complaints by contending that the prosecution withheld material witnesses whose evidence would have shed light on the issues in controversy, particularly the complainant's mother. He further argues that the investigating officer failed to recover or produce material exhibits, including the undergarments allegedly left at the scene, and generally conducted superficial investigations. It was also his contention that the failure to subject the child born to the complainant to DNA testing left unresolved the question of paternity and thereby rendered the conviction unsafe. On those premises, he urges this court to quash the conviction, set aside the sentence and allow the appeal.
6. This being a first appeal, the court is required to independently reappraise the entire record and reach its own determination, bearing in mind that it did not have the advantage of seeing or hearing the witnesses testify. The Court of Appeal in Imanyara & 2 others v Attorney General [2016] KECA 557 (KLR) restated that a first appellate court must evaluate the evidence afresh and arrive at its own conclusions, making due allowance for that disadvantage.
7. Having carefully considered the petition of appeal, the record of the proceedings before the trial court, the judgment appealed against and the appellant's written submissions, the following issues arise for determination:
1) Whether the prosecution proved the offence of defilement against the appellant beyond reasonable doubt.
2) Whether the alleged failure to call the complainant's mother, conduct DNA analysis and recover or produce certain exhibits rendered the conviction unsafe.
3) Whether there is any basis for interfering with the sentence imposed by the trial court.
8. The Court of Appeal in Olenkom v Republic [2026] KECA 798 (KLR) reaffirmed that to sustain a conviction for the offence of defilement under section 8 of the Sexual Offences Act, the prosecution must prove beyond reasonable doubt three essential ingredients, namely the age of the complainant, penetration and the identity of the perpetrator. The Court further observed that proof of age is indispensable because it determines both criminal liability and the applicable sentence; that age may be established by a birth certificate, an age assessment report, medical evidence or any other credible and reliable evidence; and that penetration may be proved by the complainant's testimony, with medical evidence serving a corroborative, rather than indispensable, role.
9. The first ingredient is the age of the complainant. The complainant (PW1) testified that she was born on 10th June 2008, and her testimony was corroborated by the birth certificate produced in evidence without objection. The charge alleged that the offence was committed between 01st April 2024 and 27th May 2024, during which period the complainant was fifteen (15) years old. I therefore find that the prosecution proved beyond reasonable doubt that the complainant was a child aged fifteen years at the material time, thereby bringing the offence within the ambit of section 8(3) of the Sexual Offences Act.
10. The second ingredient is proof of penetration. Section 2 of the Sexual Offences Act defines penetration as the partial or complete insertion of the genital organs of one person into the genital organs of another. The complainant testified that after the appellant professed his love for her, she accompanied him to his house where he removed his clothes, she removed hers, and inserted his penis into her vagina, causing her pain. She further testified that they engaged in sexual intercourse on another occasion before they were discovered together on the night of 27th May 2024. Her testimony was corroborated by the medical evidence, which disclosed findings consistent with penetration. In addition, the evidence showed that the complainant subsequently conceived and gave birth, a circumstance that lends further support to her account that she had engaged in sexual intercourse. I find the complainant's account to have been coherent, consistent and materially corroborated by the medical evidence. Consequently, I am satisfied that the prosecution proved the element of penetration beyond reasonable doubt.
11. The final ingredient is whether it was the appellant who perpetrated the offence. The complainant testified that she had known the appellant for about one and a half years before the commission of the offence, as he worked at the home of one Ombego. This was therefore a case of recognition rather than the identification of a stranger. She further testified that the appellant professed his love for her and that they engaged in sexual intercourse on more than one occasion over a period of time before arranging to meet again on the night of 27th May 2024.
12. PW2 stated that she saw the complainant and the appellant together that evening and alerted the complainant's mother. PW2 thereafter accompanied other members of the public to the appellant's residence, where the complainant was found hiding in a goat shed within the appellant's compound while the appellant was discovered concealed in a dog kennel. Those circumstances were wholly consistent with the complainant's account and significantly reinforced the prosecution's case on identity. The appellant's sworn denial did not displace that evidence or raise any reasonable doubt. I am therefore satisfied that the prosecution proved beyond reasonable doubt that it was the appellant who defiled the complainant.
13. The appellant also complained that the prosecution failed to call the complainant's mother as a witness, conduct DNA analysis and recover certain exhibits from the scene. With regard to the failure to call the complainant's mother, section 143 of the Evidence Act provides that no particular number of witnesses shall, in the absence of any provision of law to the contrary, be required for the proof of any fact. In Mutunga v Republic [2006] KECA 79 (KLR), the Court of Appeal reiterated that the prosecution has the discretion to determine the witnesses necessary to prove its case, and an appellate court will not interfere with that discretion unless it is shown to have been exercised improperly. In the present case, the complainant's mother was not an eyewitness to the acts of defilement, and the evidence of the complainant, PW2 and the medical evidence sufficiently established the charge.
14. Regarding the absence of DNA analysis, section 36(1) of the Sexual Offences Act empowers the court to direct the taking of samples for forensic analysis but does not make DNA testing mandatory. In Williamson Sowa Mbwanga v Republic [2016] KECA 147 (KLR) ,the Court of Appeal held that failure to conduct DNA analysis is not fatal where the prosecution has otherwise proved the essential ingredients of the offence beyond reasonable doubt.
15. Similarly, the failure to recover the alleged exhibits from the scene did not weaken the prosecution's case, as the offence was established by credible oral and medical evidence. I therefore find that none of the matters raised by the appellant created any reasonable doubt as to his guilt.
16. The appellant has also challenged the sentence imposed by the trial court. An appellate court will not ordinarily interfere with the exercise of sentencing discretion unless it is shown that the trial court acted on a wrong principle, overlooked a material factor, considered an irrelevant factor, or that the sentence imposed is manifestly excessive or manifestly inadequate in the circumstances. Where the sentence is lawful and the discretion has been properly exercised, an appellate court has no basis for interference.
17. The appellant was convicted under section 8(1) as read with section 8(3) of the Sexual Offences Act, which prescribes a sentence of not less than twenty years' imprisonment where the child is between the ages of twelve and fifteen years. The record, however, shows that the learned trial magistrate imposed a sentence of fifteen (15) years' imprisonment, which is below the statutory minimum prescribed by law.
18. The appellant alone appealed against both conviction and sentence, and the respondent neither filed a cross-appeal nor gave notice seeking enhancement of sentence. In those circumstances, while the sentence imposed was more lenient than that contemplated by section 8(3) of the Act, there is no basis upon which this court can enhance it in the absence of a cross-appeal or a notice for enhancement. Accordingly, I decline to interfere with the sentence imposed by the trial court.
19. Having independently re-evaluated the entire evidence on record, I am satisfied that the prosecution proved the offence of defilement against the appellant beyond reasonable doubt. The grounds of appeal are devoid of merit. I therefore find no basis for interfering with either the conviction or the sentence imposed by the trial court.
20. Accordingly, the appeal is dismissed in its entirety. The conviction for the offence of defilement contrary to section 8(1) as read with section 8(3) of the Sexual Offences Act and the sentence of fifteen (15) years' imprisonment are hereby affirmed.