A detailed analysis of the rationale and potential benefits of choosing a Commission of Enquiry as a reform measure has been made by Kirya (2011) in ‘Performing “good governance”: Commissions of Inquiry and the Fight against Corruption in Uganda’. Here is her overview:

‘The findings suggest that the global anti-corruption framework signified by the good governance agenda is hindered by various factors such as the self-interest of donors, the moral hazard inherent in aid and the illegitimacy of conditionality; all of which contribute to the weak enforcement of governance-related conditionalities. This in turn causes aid-recipient countries such as Uganda to do only the minimum necessary to keep up appearances in implementing governance reforms. National anti-corruption is further hindered by the government tendency to undermine anti-corruption by selective or non-enforcement of the law, the rationale being to insulate the patronage networks that form the basis of its political support from being dismantled by the prosecution of key patrons involved in corruption. Ad hoc commissions of inquiry chaired by judges, which facilitate a highly publicised inquisitorial truth-finding process, therefore emerge as the ideal way of tackling corruption because they facilitate ―a trial in which no-one is sent to jail. …
They also served to appease a public that was appalled by the various corruption scandals perpetrated by a regime that had claimed to introduce ―a fundamental change and not a mere change of guard in Uganda politics. Nevertheless, while they enabled the regime to consolidate power by appeasing donors and the public, they also constituted significant democratic moments in Uganda history by allowing the public – acting through judges and the media – to participate in holding their leaders accountable for their actions in a manner hitherto unseen in a country whose history had been characterised by dictatorial rule.