The UK’s Court of Appeal on Monday quashed the convictions of three black men who were arrested for robbery in the late 1970s, where the court relied on the testimony of a knowingly corrupt police officer.

The hearing in front of the Royal Court of Justice sought to overturn the convictions of Courtney Harriot, Paul Green and Cleveland Davidson, famously known to be part of the Stockwell Six. They were accused of robbing police officer Derek Ridgewell on the London underground in 1972, with Harriot serving the longest sentence of three years. Despite pleading not guilty at trial, the decision was largely based on the testimony of the British Transport Police (BTP), run by Ridgewell, leading to their arrest.

There were multiple investigations conducted by the BBC in 1973, exposing Ridgewell to be corrupt, linking further examples of wrongful convictions including the Oval Four, from the same corrupt officer. Furthermore, the BTP and Home Office were warned of Ridgewell’s corruption, including claims that he subject the men to violence and threats before trial, which was ignored by both organizations. The police officer subsequently was arrested in 1980, pleading guilty to conspiracy to steal mailbags, and died in prison in 1982.

Five decades later, upon overturning the decision, the BTP apologized for the “distress and impact” caused, however, the men exonerated have stated it has “ruined their life”. Two of the last three members of the Stockwell Six have not been traced, and the sixth member was acquitted.