In Ashok Debbarma v. State of Tripura, (2014) 4 SCC 747, the Hon’ble Supreme Court elaborated upon the concept of “residual doubt” which simply means that in spite of being convinced of the guilt of the accused beyond reasonable doubt, the Court may harbour lingering or residual doubts in its mind regarding such guilt. The Hon’ble Court noted that the existence of residual doubt was a ground sometimes urged before American courts as a mitigating circumstance with respect to imposing the death sentence, and noted as follows:
“In California v. Brown , 93 L Ed 2d 934 : 479 US 538 (1987) and other cases, the US courts took the view, “residual doubt” is not a fact about the defendant or the circumstances of the crime, but a lingering uncertainty about facts, a state of mind that exists somewhere between “beyond a reasonable doubt” and “absolute certainty”. The petitioner’s “residual doubt” claim is that the States must permit capital sentencing bodies to demand proof of guilt to “an absolute certainty” before imposing the death sentence. Nothing in our cases mandates the imposition of this heightened burden of proof at capital sentencing.
But, in between “reasonable doubt” and “absolute certainty”, a decision-maker’s mind may wander, possibly in a given case he may go for “absolute certainty” so as to award death sentence, short of that he may go for “beyond reasonable doubt”. Suffice it to say, so far as the present case is concerned, we entertained a lingering doubt as to whether the appellant alone could have executed the crime single-handedly, especially when the prosecution itself says that it was the handiwork of a large group of people. If that be so, in our view, the crime perpetrated by a group of people in an extremely brutal, grotesque and dastardly manner, could not have been thrown upon the appellant alone without charge-sheeting other group of persons numbering around 35. All the element test as well as the residual doubt test, in a given case, may favour the accused, as a mitigating factor.” While the concept of “residual doubt” has undoubtedly not been given much attention in Indian capital sentencing jurisprudence, the fact remains that this Court has on several occasions held the quality of evidence to a higher standard for passing the irrevocable sentence of death than that which governs conviction, that is to say, it has found it unsafe to award the death penalty for convictions based on the nature of the circumstantial evidence on record. In fact, this question was given some attention in Mohd. Mannan v. State of Bihar, (2019) 16 SCC 584, where the Hon’ble Court found it unsafe to affirm the death penalty awarded to the accused in light of the nature of the evidence on record, though the conviction had been affirmed on the basis of circumstantial evidence. Sudam v. State of Maharashtra, (2019) 9 SCC 388