After two years and two months waiting in jail, one of Kenya’s best known white aristocrats finally takes the stand this week to defend himself against charges of murdering a black poacher on his family estate.

For the Hon Thomas Cholmondeley, grandson of the late Lord Delamere and heir to both the title and one of the country’s biggest estates, it has been an agonising wait.

A life of servants, champagne, safari parties and private planes was no preparation for being the only white man among 3,600 prisoners in Kamiti maximum security jail, which he describes as “like living inside a greasy saucepan infested with rats and cockroaches”.

Crowds are expected to pack the wooden-panelled Nairobi high court to see the Old Etonian tell for the first time his version of events surrounding the death of Robert Njoya. Among them will be one person for whom the wait has seemed even longer – Sally Dudmesh, his girlfriend.

“It’s been like living in hell,” said Dudmesh, a British jewellery designer who runs a boutique in the Kenyan capital. “Tom and I had this idyllic life; then from one day to the next everything went horribly, horribly wrong.”

At 46, Dudmesh is no stranger to tragedy. Two of her previous lovers were murdered in Kenya: Tonio Trzebinski, a Polish aristocrat who was shot through the heart in 2001, and Giles Thornton, a British artist killed in a beach house.

Her best friend was Emma McCune, an aid worker who was on her way to a dinner party at Dudmesh’s house in Nairobi in 1993 when she was killed in a mysterious car accident. She was six months pregnant. She also had a fling with Carlos Mavroleon, who went off to fight with the Afghan mujaheddin and was found dead in his hotel room in Peshawar.

“I feel cursed,” says Dudmesh. “Outsiders see our life-style as whites in Kenya as charmed and, yes, it can be magical waking up to the animals and the big skies or under the stars at night; but you pay such a big price for the beauty.”

Her life certainly looks privileged. During the week she lives in the Ngong Dairy, which was used as Karen Blixen’s home in the film of her book Out of Africa. Weekends are spent in Jersey Hall, a seven-bedroom converted cattle shed on Delamere’s 58,000-acre estate in the Great Rift Valley.

Although she met Cholmondeley 10 years ago on a trek in Mongolia, he was then newly married. They got together only in 2005 when his wife asked Dudmesh to arrange a camel safari for him. “It was a scandal,” she admits.

Cholmondeley had just been on trial for murdering a game warden on the estate after saying that he had acted in self-defence, believing the man to be an armed intruder.

Less than a year later, on May 10, 2006, Dudmesh was in Nairobi when she received a text message from Cholmondeley to say he had a problem. A poacher had been killed on the estate and Cholmondeley was once again in police custody. “I didn’t believe it,” she said.

With a friend, he had stumbled across a group of poachers and fired at their dogs, as is common practice. Njoya was found bleeding from his buttocks and Cholmondeley took him to hospital, where he later died.

Within four days of Njoya’s death, Cholmondeley was charged with murder. “The hardest thing was we had had a year of total bliss like we’d found our other halves; then this happened.” Coming so soon after the previous killing, it provoked public outrage and tribesmen blocked the highway to prevent produce being transported off the Delamere estate. Much of the white community turned against Cholmondeley, whom they saw as rocking the boat.

“People are very judgmental,” said Dudmesh. “I would go into restaurants and could hear people whispering, ‘That’s Tom Cholmondeley’s wife’.”

She also had to get used to Kenyan prisons. “I never imagined going in and out of jail in a million years,” she said. “I’m a jeweller who deals with beautiful things.”

She has managed to get him supplies of food and books and even a cake for his 40th birthday last month. Tomorrow she will take in a suit and tie ready for his court appearance.

One of the hardest things for Cholmondeley has been not seeing his sons, Henry, 8, and Hugh, 10, who moved to Sussex with their mother shortly after his second arrest.

The last case to grip Kenyan society in this way was the 1941 trial of Sir Jock Delves Broughton, who was accused of murdering the playboy Earl of Erroll who had planned to run off with Diana, Broughton’s young wife. Broughton was acquitted but committed suicide a year later.

Diana went on to marry Lord Delamere, becoming Tom Cholmondeley’s stepgrandmother.

The trial exposed the alcohol and drug-fuelled wife-swapping of Kenyan whites known as the Happy Valley set and was dramatised in the film White Mischief starring Greta Scacchi.

Cholmondeley and Dudmesh have not dared to make plans for what will happen if he is acquitted; nor does she think about the case going the other way. “I know Tom isn’t capable of killing anyone and I have to believe in justice,” she said.

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