The high court in Kenya has dismissed a case against four men who were accused of involvement in burning to death 33 people in a church in January 2008.
The judge said the prosecution had failed to make its case against the men, who were the only people charged with murder over the attack in Eldoret.
Justice David Maraga also blamed shoddy police investigating in his ruling.
Eldoret is in the Rift Valley, which was hardest hit by weeks of bloodshed after the disputed December 2007 poll.
The four suspects were charged two months after the town’s church was torched by a mob on New Years Day 2008.
Justice Maraga criticised the police and prosecuting authorities as he announced the case would be dropped on Thursday in a 45-page ruling in Nairobi.
“The events preceding the commission of this offence cannot have eluded the police as clouds for the gathering storm were there for all to see,” he said, reported AFP news agency.
“I am not a politician but I am only a judge and a Kenyan who is just as outraged at the casual manner in which we are handling serious issues like insecurity in this country and by the attitude of our police force in the face of serious crime,” the judge added.
Violence erupted after the December 2007 presidential poll amid accusations that then opposition leader Raila Odinga was being robbed of victory by the incumbent, Mwai Kibaki.
A peace deal between the political rivals resulted in a coalition government and an end to last year’s disorder, which left an estimated 1,500 people died and 300,000 displaced.
But the unity administration has become increasingly strained in recent months amid claims by Mr Odinga, who is now prime minister, that his party is being sidelined.