Peru's Constitutional Court (Tribunal Constitucional, or TC) has overturned the 15-year prison sentence handed to former President Ollanta Humala and ordered that the criminal investigation against him be closed for good. The ruling, published on July 31, 2026, in the official government gazette El Peruano, wipes out the entire legal process that led to his conviction earlier this year. (El Peruano)

The TC upheld Humala's habeas corpus petition — a legal filing that in Peru goes beyond challenging unlawful detention and can be used to question the fairness of criminal proceedings themselves. The court found that the principle of legality had been violated during his prosecution. Legality, in this context, means that criminal liability and punishment must be based on clearly established law applied through proper procedures. Rather than simply sending the case back for a new trial, the TC directed that the investigation be archived — officially closed. (Deutsche Welle)

The original sentence came from the Tercer Juzgado Penal Colegiado Nacional (Third National Collegiate Criminal Court) on April 15, 2026. That court convicted Humala in a corruption case, making him one of several former Peruvian presidents facing or serving sentences related to graft. The TC's ruling now removes that conviction from the legal record entirely. (El Peruano)

The order to close the file is what makes this ruling unusual. A typical appellate court reversal would allow prosecutors to retry the case. By archiving the investigation instead, the Constitutional Court blocks further pursuit of the matter within the scope of the original case. (Panamericana)

The court's reasoning turned on the legality principle. The full details of which specific procedural defects triggered the finding are in the court's published resolution. What the ruling illustrates is how broadly Peru's Constitutional Court interprets the habeas corpus writ — using it here not to prevent someone from being locked up, but to undo a completed conviction.

This is not the first time the TC has clashed with the ordinary judiciary. Peru's legal system has a built-in tension: the Constitutional Court serves as the ultimate interpreter of constitutional rights, while the National Collegiate Criminal Courts handle serious offenses. When the TC finds that constitutional principles were violated during a criminal trial, its decisions bind lower courts and can nullify their work entirely.

Humala's case is part of a wider pattern of judicial proceedings against former Peruvian heads of state. He was convicted alongside a group of ex-presidents caught in various stages of the justice system. The TC's decision reduces that group by one, though each former president's legal situation remains governed by their own separate proceedings.

The broader context here involves the relationship between Peru's anti-corruption apparatus and its constitutional judiciary. When the Constitutional Court throws out a corruption conviction on legality grounds, it raises a legitimate question: were the problems caused by individual prosecutors and judges making mistakes, or by structural flaws in how these cases are built? That distinction matters. Isolated errors can be corrected on retrial. But if the TC's reasoning points to systemic defects in how corruption cases are prosecuted, the implications extend well beyond Humala.

Among the things worth watching is whether prosecutors try to pursue the matter through alternative legal channels despite the archive order, and whether the ruling triggers broader review of pending corruption cases that share procedural features with Humala's.

The decision is final. The TC is Peru's court of last resort for constitutional matters, and no further appeal is available within the domestic legal system.