The Supreme Court of India has ruled that a High Court cannot independently invoke suo motu revisional powers to enhance a criminal sentence when the appeal has been filed solely by the convict. In Nagarajan v. State of Tamil Nadu, the Madras High Court had, of its own accord, added a conviction under Section 306 IPC and increased the sentence from three years to five in an appeal by the accused—despite no appeal from the State, victim, or complainant. A bench of Justices B.V. Nagarathna and Satish Chandra Sharma set aside the added conviction and sentence, reaffirming that an appellate court in an appeal by the accused may only acquit, order retrial, reduce the sentence, or maintain it—but cannot enhance it unless the prosecution or victim has filed a separate appeal.

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