Gu Kailai, the former wife of disgraced Chinese politician Bo Xilai, had confessed to killing British businessman Neil Heywood, according to China’s state-controlled Xinhua news agency.
She blamed her actions on a “mental breakdown” but would "accept and calmly face any sentence."
Four senior police officials earlier admitted they concealed evidence linking Gu to the killing.
The murder trial lasted only one day.
Heywood’s body was found in the city of Chongqing November 2011.