The Supreme Court on Wednesday said that while granting pardon, the President or a governor must take into consideration the impact of such clemency on the families of the victims also.
The judgment is important because the mercy petition of the convicted mastermind of the 2001 attack on the Indian Parliament Mohammad Afzal Guru is pending with President A P J Abdul Kalam.
A bench comprising Justices Arijit Pasayat and S H Kapadia, overturning a pardon granted by the governor of Andhra Pradesh to a convict in a murder case, said, ''Pardon obtained by fraud or granted by mistake will invite judicial review.''
The then Andhra governor Sushil Kumar Shinde had pardoned Congress activist Gowru Venkata Reddy, who was convicted in a murder case.
The court also said the rule of law was supreme.
The court also ruled that grant of clemency was not an act of grace but a matter of performance of official duty.
And if it is based on a political or an irrelevant consideration, then such an exercise is in derogation of the constitutional authority given under article 72 or 161.
The court, however, permitted governors to reconsider decisions taking into consideration the material placed before them.
The mercy petition of Afzal Guru may be affected by the judgment.
Political leaders and activists have been trying to create pressure to seek clemency for him. But the families of the policemen, who were killed in the attack, are strongly opposed to pardoning him.