With a crowd overflowing and standing in the corridors, the high-profile case of Cholmondeley, son of the fifth Baron Delamere, began at Nairobi High Court amid fears it will re-open colonial-era wounds.
“We shall present evidence to prove beyond reasonable doubt that the accused by his unlawful act with malice aforethought caused the death of Robert Njoya," prosecutor Keraiko Tobiko told judge Muga Apondi in his opening statement.
Mr Tobiko said the defendant deliberately shot and killed Njoya, 37, with a high-powered hunting rifle while he was running away and then tried to cover up the crime by tampering with evidence at the scene.
"The accused has no legally recognized justification or excuse for causing the death of the deceased," he said, as Cholmondeley, 38, looked on impassively sitting squeezed between two burly police officers.
The prosecutor said that Cholmondeley's claim to have been protecting himself and his property from trespassers and poachers was not an excuse for killing someone.
“The accused attacked the deceased and his companions as retaliation or revenge for trespassing and poaching on his land," Mr Tobiko told the court. "He was not under attack or threat from the deceased or his companions".
Cholmondeley has pleaded not guilty to murder, maintaining he shot Mr Njoya in self-defense after the man and several companions suspected of poaching set dogs on him on his vast Delamere ranch in Kenya's central Rift Valley in May.
Second case
It’s the second case in which the Eton-educated Cholmondeley, heir to one of the nation's largest white landowners, has been accused of killing a Kenyan on the ranch, about 90 kilometres (55 miles) northwest of Nairobi.
He pleaded not guilty in the first as well, claiming to have killed a wildlife ranger he mistook for a thief in self defense. That charge was dropped for lack of evidence last year.
Cholmondeley's cases have received particular attention due to his family history. His great-grandfather, Hugh, the third Baron Delamere, was a key player in Britain's colonisation of Kenya who oversaw the settlement of the so-called "white highlands".
His grandfather achieved notoriety in 1955 when he married Diana Broughton, a central figure in the murder of her lover, Josslyn Hay, the 22nd Earl of Errol, on the outskirts of Nairobi in 1941.
There have been threats of violent retaliation and land seizures, including from government officials, if Cholmondeley goes free again.
Land reform
The two killings have reignited more than a century of resentment between native Africans and white settlers, mainly of British origin, with some Kenyans arguing that the country should adopt Zimbabwe-style land reforms.
But while the shootings have reopened claims of white land-grabbing, they have also highlighted what expatriates say are legitimate security fears, after the murders of four foreign residents since 2004.