Kenya's president has announced the formation of a commission to investigate the country's disputed December elections. But as Derek Kilner reports from Nairobi, there are doubts about how effective such an investigation will be.

President Mwai Kibaki's office released a statement saying the commission will be headed by Johann Kriegler, a South African judge who headed that country's electoral commission during its first post-apartheid elections in 1994.

The investigative commission is set to pay particular attention to the conduct of the presidential election. Mr. Kibaki's main opponent in the presidential race, Raila Odinga, claims the vote was rigged, and international observers have said the results were not credible.

The country's main parties had earlier agreed on the need for an inquiry into the elections, during negotiations mediated by former U.N. Secretary-General Kofi Annan.

The commission is expected to hold public hearings to question officials who organized the election. There has been mounting pressure from civil society groups in recent days for the chairman of Kenya's electoral commission, Samuel Kivuitu, to resign, and for the body to be restructured.

Civil society leaders have welcomed the inquiry, while warning of the failures of similar commissions in the past. Charity Ngilu is a top member of Odinga's Orange Democratic Movement, echoed that concern.

"Bearing in mind that commissions have been appointed before, by Kibaki in particular, and bearing in mind that they have always come out with their recommendations after their work is done and that no action, no implementation of the recommendation is done," said Ngilu. "This may just be another of those commissions."

Local media have reported that the structure of the inquiry will be similar to the Goldenberg Commission that investigated a corruption scandal from 2003 to 2005. That commission's recommendations were largely ignored.

Political analyst Mutahi Ngunyi says that the commission could be counterproductive, increasing tensions between the partners in the country's fragile power-sharing arrangement.

"This commission is completely unnecessary because if the conclusions of the inquiry are that Raila won the election we will not be in a good place," said Ngunyi. "If it concludes that Kibaki won the election, the results will also not be good for the country. Since now there is a power-sharing deal, we don't want to change the situation."

Other members of the six-person commission include representatives of Kibaki's Party of National Unity, and opposition leader Raila Odinga's Orange Democratic Movement, as well as a judge from Tanzania and an international elections expert from Argentina.