The family of Mark Duggan, whose fatal shooting by a police marksman sparked nationwide riots, have won permission to go to the Court of Appeal over a finding that he was "lawfully killed".
Led by Mr Duggan's mother Pamela, they are challenging a decision by three High Court judges that an inquest jury was legally entitled to bring in its 8-2 majority verdict.
The inquest jury decided last January that the 29-year-old was lawfully killed by a police marksman in Tottenham, north London, in August 2011.
Giving the appeal the go-ahead, Lord Justice Sales declared there was "an arguable case" the jury was applying the wrong test when it decided the officer who fired the fatal shot held an "honest belief" Mr Duggan was holding a gun and had acted in self defence.
Eight of the jurors decided the belief was honest, even though Mr Duggan was not armed at the time and had thrown down the firearm shortly before meeting his death.
The judge cautioned he was not saying the appeal must succeed but was granting permission "on the basis that there is a real prospect of success".
The judge said: "I also consider a further compelling reason for the grant of permission is that the shooting dead of a suspect by police is always a matter for careful scrutiny."
Local MP David Lammy welcomed the judge's decision, saying there was "a strong sense in the local community that a number of questions about Mark Duggan's death remain unanswered".
If the family win their appeal, it is likely the "lawful killing" verdict will be quashed and there will be a fresh inquest. The Duggan family have previously indicated they want an open verdict.
Armed officers intercepted the minicab Mr Duggan was travelling in on the basis of intelligence that he was part of a gang and had collected a gun. He was shot twice by an officer known as V53. One of the hits was fatal.
The jury concluded Mr Duggan, who jumped from the taxi, had dropped the firearm on to grass as soon as the minicab came to a stop - but the officer "honestly believed" Mr Duggan still had a gun at the time he was shot.
Hugh Southey QC, appearing for Mrs Duggan, submitted that coroner Judge Keith Cutler wrongly directed the jury to apply the "purely subjective test of honest belief", which was the criminal law test for self defence.
Mr Southey argued the jury should have been asked to apply the objective test of "whether V53's mistaken belief was a reasonable one".
The QC submitted the coroner's misdirection was contrary to the duty under Article 2 of the European Convention on Human Rights to carry out an effective investigation into Mr Duggan's death.
The court heard the outcome of the appeal could be decisively influenced by the case of "Da Silva v the UK".
The case concerning the fatal shooting of Brazilian national Jean Charles de Menezes by police in the London Underground after being mistaken for a terrorist is pending before the European Court of Human Rights in Strasbourg.
The judge refused to stay the Duggan appeal until the outcome of the Da Silva hearing. He said if Duggan was heard first the ruling might contribute to the Da Silva case.
If Da Silva reached judgment first, it would be open to the parties in Duggan to decide whether or not to go ahead with the appeal, depending on the outcome in Strasbourg.
Mrs Duggan has said she remains "deeply distressed" about her son's death and the inquest verdict.
His aunt Carole, 53, from central Manchester, said the family feel "extremely let down and disappointed" and that they are being blamed for the "uprising" of the 2011 riots which followed the shooting.