PC Blakelock's son Kevin says those responsible for his father's murder have nowhere to hide.
He said: “People who do horrific acts like this, should not be able to sleep well at night. They should always have a thought in their mind that justice will be served one day and the knock will come on the door.”
The family hope despite the passage of time that this new appeal for information will help to push the investigation forward. Anyone with information can contact Crimestoppers on 0800 555 111 or theMetropolitan Police Incident Room - 020 8203 4617.
PC Keith Blakelock's son Lee has said that the main point he wanted to get across in a rare television interview for the family was that his father "was a person".
He said: “Keith was a person. Yes he was a uniform and that’s what they attacked and they killed a police officer but he was a family man. I always wanted to join the police, since before my Dad died.
"It was something as a kid I always wanted to do. I’m immensely proud of taking over the mantle of PC Blakelock.”
Anyone with information can contact Crimestoppers on 0800 555 111 or the Metropolitan Police Incident Room - 020 8203 4617.
In a rare television interview PC Keith Blakelock's widow, Elizabeth, has spoken of the torment caused by listening to evidence on how the officer was killed and said the attackers had deprived her sons of a father.
Elizabeth said: "You wouldn’t do that to an animal, let alone a human being. That human being was lying there begging you, please, begging you for his life. And still, you went at him with whatever implements, weapons. You’ve deprived these boys of a father. "
The family of PC Keith Blakelock have waited 29 years for justice and their wait goes on. Anyone with information can contact Crimestoppers on 0800 555 111 or the Metropolitan Police Incident Room - 020 8203 4617.
Eyewitness 'John Brown', a former member of the Park Lane Boys gang, who accepted a caution for assaulting his partner in 2010, said defendant Nicky Jacobs used a machete with a 12-inch blade during the attack on Pc Keith Blakelock.
He told the jury that he himself had kicked the officer some 10 times after he went to the ground.
Asked why, he said: "Looking back on it I don't know...It was the excitement of the situation, I just rushed forward and kicked him about ten times."
The witness said he had been paid a £5,000 reward by the police after giving a statement during a renewed police investigation into the killing in 1993.
Asked by Richard Whittam QC, for the prosecution, what the officer was doing during the attack, Mr Brown said: "What I saw, he was trying to curl up into a ball, I suppose to protect himself somehow.
"Did he say anything?" Mr Whittam asked.
"I just heard heard screams of 'help, help, help'."
PC Blakelock curled up in a ball and screamed for help as a mob hacked him to death during the Broadwater Farm riots, an eyewitness has told the Old Bailey.
Using the pseudonym John Brown and with his voice distorted by a modulator to protect his identity, the witness described how he saw the killing on the estate in Tottenham, north London, on October 6 1985.
He explained that he had seen Nicky Jacobs, 45, stabbing PC Blakelock with a machete between two and four times as the frenzied mob took part in a "free for all".