This week, the Supreme Court acquitted Surendra Koli in the rape and murder case of a teenage girl – one of the many that arose in the Nithari killings – overturning its own 2011 decision.The ruling followed Koli’s curative petition – an extraordinary legal remedy in the Indian judicial system. In its order, the court cited a “fundamental defect” in its earlier ruling, saying it conflicted with Koli’s acquittals in 12 other Nithari cases, all based on rejection of the same evidence.Here’s what a curative petition is.What is a curative petitionIn the criminal justice system, trial court orders can be appealed in appellate courts — the high courts and the Supreme Court. Once an appeal is dismissed, the next remedy is a review petition, which asks the same court to reconsider its decision based on specific grounds, such as discovery of new evidence or a mistake on the face of the record.A curative petition is an extraordinary remedy filed when there’s a violation of natural justice. It’s not a second review and cannot be heard like one. It can be filed only after the review remedy is exhausted, and only when certain facts point to serious injustice or errors that led to an unfair outcome.The contours of the curative petition were shaped by the 2002 case Rupa Ashok Hurra vs Ashok Hurra. Invoking its inherent powers under Articles 142 and 137 of the Constitution, the court held that an aggrieved party could seek relief in cases of gross abuse or miscarriage of justice.While Article 142 empowers the court to “make such orders as are necessary for doing complete justice”, Article 137 recognises the court’s power of review and its limits.However, the court added a rider – that unless “very strong reasons exist”, such petitions should not be entertained.The procedure to file and list curative petitions is laid down in Order XLVIII of the Supreme Court Rules, 2013.Story continues below this adWhat happened in the Nithari caseThe allegations against Koli date back to 2005 and 2006, when several women and children were reported missing in Nithari village in Noida’s Sector 31 and skeletal remains were found in a drain and on an open strip of land behind a house owned by Moninder Singh Pandher. The curative petition pertains to one of the first cases to be tried – the murder of a minor who went missing in 2005.In 2009, a trial court convicted both Koli and Pandher of rape and murder and sentenced them to death. The sentence against Koli was upheld by the Allahabad HC and the Supreme Court, although Pandher was acquitted.The court also dismissed his review petition. His mercy petitions to the Uttar Pradesh Governor and the President of India were rejected, prompting him to file a curative petition.In 2015, the Allahabad High Court upheld the conviction but commuted his sentence to life imprisonment citing “inordinate delay” in deciding his mercy petitions.Story continues below this adMeanwhile, a lower court tried and convicted Koli in 12 other Nithari cases between 2010 and 2021, but the Allahabad High Court acquitted him in 2023. The state’s appeals against these acquittals were dismissed by the Supreme Court in July 2025.Significantly, these acquittals were based on the same evidence – his 2007 confession before a magistrate and the recoveries made in 2006. In its 2023 order, the Allahabad HC held that the confession could not be considered voluntary or reliable since Koli had been in continuous police custody for 60 days with no access to a lawyer. The confession also referred to him being tutored and tortured, the court said.It was on this basis that the court acquitted Koli. In its ruling, a three-judge Bench of Chief Justice B R Gavai, Justice Surya Kant and Justice Vikram Nath called it an “exceptional case” and said his conviction in this case, based on the same evidence that led to his acquittal in 12 others, cannot lawfully co-exist.Intervention in such a case was a constitutional duty, the court said. “We, therefore, entertain this petition to preserve the purity of this Court’s process and to vindicate the rule of law,” the Bench said.Story continues below this adAccording to the court, the various Articles of the Constitution together present a “narrow jurisdiction” that may be invoked “to correct a grave defect”. “The guiding principle for the exercise of curative jurisdiction is the duty of this court to avert manifest injustice,” it said.Its objective, the SC said, was not to reopen evidence as in a second appeal “but test the conviction against the legal defects” that led the Allahabad High Court to acquit Koli in 12 cases based on the same material. From infirmities in the way Koli’s ‘confession’ was recorded to faults in how alleged recoveries were shown to have been made, the court pointed to several “fundamental defects” and allowed the curative petition.Past cases of curative jurisdictionIn 2014, the SC commuted the death sentence of 1993 Delhi bomb blast convict Devinder Pal Singh Bhullar to life imprisonment, citing the eight-year delay in disposing of his mercy petition and his mental illness.Bhullar had been sentenced to death in 2001 for his role in the blast that killed nine people. The sentence was upheld by the high court and the Supreme Court, and his review petition was rejected.Story continues below this adIn 2013, the court allowed a curative petition filed by the National Commission for Women in a domestic dispute case. This came four years after the court held that in a domestic dispute, a mother-in-law kicking her daughter-in-law or threatening her with divorce did not amount to cruelty.In 2015, the court dismissed a curative petition filed on behalf of Yakub Memon, convicted in the 1993 Bombay serial blasts case. The petition challenged Memon’s conviction, but the court said the ruling had no flaws.Memon was hanged on July 30, 2015, in Nagpur jail.In 2023, the court dismissed a curative petition filed by the Union government seeking additional funds from Union Carbide Corporation’s successor firms for victims of the 1984 Bhopal gas tragedy. The government had sought re-examination of the 1989 ruling that set compensation at Rs 750 crore.In its ruling, the court said it found no legal basis to revisit the claim after three decades and warned that doing so could open up Pandora’s box.