Kofi Annan has urged the Kenyan government to set up a tribunal for people accused of involvement in violence after last year's elections.
The former UN secretary general brokered a power-sharing deal which ended the violence in February.
Establishing such a tribunal was a central recommendation of a commission headed by a senior judge, Philip Waki, which submitted its report last week.
The commission found that politicians on all sides had stirred up violence.
Mr Waki also said that the police had used excessive force against protestors.
The commission gave Mr Annan a sealed envelope containing the names of suspects and he told the BBC he would pass on the information to prosecutors at the appropriate time.
"I think it is important that the government acts on it," he told the BBC's Network Africa. "The victims demand justice too."
"The tendency sometimes to protect the perpetrators for the sake of peace - 'forget and let's move on' - doesn't help society. Impunity should not be allowed to stand."
More than 1,500 people were killed and some 300,000 more fled their homes after then opposition leader Raila Odinga said he had been cheated of victory by President Mwai Kibaki.
Under the deal brokered by Mr Annan, Mr Odinga became prime minister and his Orange Democratic Movement took an equal share of cabinet posts with Mr Kibaki's party.
Mr Annan dismissed the idea that the Kenyan example had set a dangerous precedent for Africa, by encouraging the idea that even if you lose you can still enter a power-sharing coalition.
"The concept of winning or losing elections is something that we should internalise," he said.
"We cannot go and create problems and expect to share power."
He said he thought that Mr Kibaki and Mr Odinga had both gone into the elections hoping to win, but the vote had resulted in an "almost perfect political gridlock".
"I had come the conclusion during the negotiations that any attempt to re-run the elections, to re-tally, to re-count, would have led to more killings, and there was no certainty that either side would accept the results," Mr Annan said.