A bench headed by Justice A K Patnaik dismissed the plea of Singh, a gangster-turned-politician from Bihar, who had approached the apex court against his conviction and life imprisonment in the murder case.
Singh, who was the leader of the then Bihar People's Party (BPP), was accused of inciting a mob accompanying the cortege of a BPP leader to lynch Krishnaiah on December 5, 1994. The BPP is now defunct.
The officer was pulled out of a car, beaten up mercilessly and then shot dead.
Singh, a former MP from Sheohar, was awarded death sentence under Sections 302 (murder) and 109 (abetment of offence) of the Indian Penal Code by Additional District and Sessions Judge R S Rai had on October 3, 2007.
However, the Patna High Court in its December 2008 verdict had commuted Singh's death penalty to life sentence, against which he had moved the apex court.