Mr Sidhu had allegedly hit a 65-year-old man, Gurnam Singh, on the head during an argument on a road in Patiala on December 27, 1988. Gurnam Singh died in hospital of a haemorrhage.
In 2007, the Supreme Court suspended Mr Sidhu's sentence and granted him bail after he appealed his conviction by the Punjab and Haryana High Court. The suspended sentence enabled him to contest the Lok Sabha bypolls from Amritsar.
"There is no evidence that the person in the road rage died because of a heart attack," said the Congress government, contradicting its own minister. Mr Sidhu, 54, had argued in court that Gurnam Singh died of a heart attack.
The government also told the bench of Justice Jasti Chelameswar and Justice SK Kaul that Mr Sidhu's statement denying his involvement in the incident was false.
"There is not a single evidence that suggests that the cause of death was a cardiac arrest and not brain haemorrhage. The trial court verdict was rightly set aside by the high court. Accused A1 (Navjot Singh Sidhu) had given feisty blow to deceased Gurnam Singh leading to his death through brain haemorrhage," the state government told the judges.Officials say the government had no choice but to oppose the minister in court. After arguing against Mr Sidhu in the high court, it could not change its stand before the Supreme Court.A trial court had discharged Mr Sidhu but the High Court reversed it, saying that Gurnam Singh had died of a brain injury, and sentenced him to three years in jail for culpable homicide.
Mr Sidhu, former cricketer and commentator, is currently out on bail. He is in charge of the tourism and culture ministry.