Nicky Jacobs has been freed from prison after he was cleared of the murder of Pc Keith Blakelock during the 1985 Tottenham riots.
The 45-year-old was driven from Belmarsh prison in south east London this morning after administrative processes delayed his release.
Speaking outside the prison, his lawyer Tony Meisels said his client was "relieved" to be free after the four-year ordeal.
"Questions need to be asked at the very highest levels of the Crown Prosecution Service and the police as to why this prosecution was ever brought," Mr Meisels added.
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What a year it's been full of ups and down, turmoil and change and it seems events here in London have got the entire nation talking.