David Oloo Onyango was serving a five-year sentence in Kamiti Main Prison. He had a right under the law to have his prison sentence reduced by one third if he was of good conduct in prison. The Commissioner of Prisons denied Oloo this right.
Oloo moved to the High Court to challenge the decision of the Commissioner of Prisons. The High Court dismissed his challenge. His advocate, then a leading human rights defender, now Governor Kiraitu Murungi moved to the Court of Appeal. The main challenge to the decision of the Commissioner of Prisons was that it was made in violation of the Rules of Natural Justice. That is, the Commissioner of Prisons did not notify Oloo in writing of his intended action and he did not give Oloo an opportunity to defend himself.