Obado “orchestrated a plot to eliminate Otieno,” Judge Cecilia Githua said as she read her ruling, which was broadcast live on television.

He “provided motive, instigation and funds to finance the criminal enterprise.”

Obado’s former personal assistant, Michael Oyamo, “facilitated the execution” and former county clerk Caspal Obiero “ensured logistical support and concealment to avoid detection of the crime,” the judge added.

All three are now detained awaiting sentencing.

“We are happy with the conviction. We believe that justice has finally been done for Sharon,” said a lawyer for the victim’s family.

News of her murder gripped Kenyans at the time after a Nation Media Group journalist, Barack Oduor, said Otieno had contacted him about her affair with the then governor.

The two met and were later kidnapped, but Oduor said he managed to escape the speeding car.

Two days later, Otieno’s body was discovered with evidence that she may have been raped and stabbed in the neck, abdomen and back.

The journalist’s account of the kidnapping became a crucial clue in the investigation.

Police tracked the vehicle used by the kidnappers.

Its tracking device had been deactivated on the day of the alleged kidnappings and reactivated the next day in a “well-calculated measure by the killers to conceal the movement of the vehicle in question,” said the chief prosecutor at the time, Noodin Haji, in a 2018 statement.

The investigation established that there had been an “intimate relationship” between Obado and Otieno, which “subsequently led to a pregnancy of the deceased that did not leave the governor happy,” he added.

In 2018, Obado had said he had nothing to do with the murder. His lawyer told the BBC the matter was widely acknowledged and there was no shame or malice.

But the court rejected this version.

During the trial, the prosecution called 42 witnesses and relied heavily on circumstantial evidence to show that the former governor and his two co-accused had worked together to organize Otieno’s murder, Kenya’s Star newspaper reports.