Andrew Fastow, the former finance chief at Enron, has received a six-year jail sentence for his role in the collapse of the energy giant.

US District Judge Ken Hoyt showed leniency towards Fastow, cutting his originally plea-bargained 10-year sentence by four years.

It was Fastow’s testimony, which helped the government convict former Enron bosses Jeff Skilling and Ken Lay

Hoyt said Fastow had given ‘exceptional’ assistance to prosecutors, had pledged to help victims and had shown remorse.

Fastow made an anguished statement before hearing his sentence, during which he expressed his shame, pledged to work for redemption and apologized to the victims of the Enron fraud and to his friends and family.

‘I failed them,’ he said.

He is expected to be out of jail before his 50th birthday.