Nicky Jacobs, who has always maintained that he was not involved in the killing of PC Blakelock, repeated his innocence on BBC's Newsnight, which airs tonight on BBC Two at 10.30pm.
Mr Jacobs, 45, was jailed in 1986 for throwing petrol bombs at police during the 1985 Broadwater Farm riots.
He was later implicated in murder of PC Blakelock, who was stabbed 43 times as he tried to protect firefighters tackling blazes during the riots.
Mr Jacobs told the programme that rap lyrics relating to the murder that were found in his cell in 1988 were not a confession.
– Nicky Jacobs
I didn't kill PC Blakelock - I wasn't in that group that heard about firemen at the shop or whatever.
It is just fate on my behalf that turned out to be good. I wrote this rap poem and they're trying to say it is a confession - all that it is, is what was played out in the press - they talk about this baying mob attacking him and all this and trying to chop off his head. All that I just got from the press.
That's why you just see 'we, we' and that are referring to Tottenham. My only thing was saying 'I had one intention and I wiped off my knife'.
Three witnesses told the Old Bailey that they saw Jacobs take part in the attack, but his defence team questioned their credibility.
After deliberating for four hours, the jury returned a not guilty verdict.
Nicky Jacobs, who was cleared last week of the 1985 killing of PC Keith Blakelock, has given his first interview since being released from prison.
He told BBC's Newsnight that if he were a member of PC Blakelock's family: "I would be outside the courts, petitioning. I would want that (justice)."
"If I had to sit down in a court for six weeks and hear that so called justice about someone else then I would be angry and disappointed at the system and the establishment my husband died for," the 45-year-old told the programme.
"That's me personally, " he added. "Not taking nothing away from PC Blakelock's family and how they feel."
Mr Jacobs, who was 16 at the time of the Broadwater Farm riots, was charged with the policeman's murder last year and remanded in custody.
A jury at the Old Bailey last week found him found not guilty of murder and manslaughter.
Nicky Jacobs embraced his friends and supporters as he was released from Belmarsh prison today.
Jacobs, wearing a brown leather jacket, shook hands with his solicitor before greeting his friends just a day after he was cleared of murdering Pc Keith Blakelock in 1985.
He was subsequently driven away in a silver saloon car.
The 45-year-old's lawyer said his client was "relieved" to be free after his ordeal.
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.
A man who was cleared of murdering PC Keith Blakelock in 1985 is expected to be released from prison today.
Nicky Jacobs' supporters said he was kept in Belmarsh jail last night as the administrative offices had closed.
He was found not guilty yesterday of stabbing PC Blakelock to death during the Tottenham riots nearly 30 years ago.
The officer was attacked by an armed mob after his unit was deployed to protect firefighters tackling a blaze on the Broadwater Farm estate in north London on the night of October 6 1985.
Mr Jacobs, who was 16 at the time, was the seventh person to be charged with the officer's murder but no-one has been brought to justice for the killing.
Sir Bernard Hogan-Howe paid tribute to the wife of Keith Blakelock today as he said efforts to find those responsible for the policeman's murder will not stop.
Jacobs, 45, was cleared of the murder of Pc Blakelock who died at Broadwater Farm in 1985 after suffering multiple stab wounds.
"The patience and determination that Keith's widow, Elizabeth, has shown over the years as she has pushed for answers about her husband's murder has been inspirational. She so richly deserves those answers and justice," the Metropolitan Police Commissioner said.
"We accept the decision of the jury and our work to bring those responsible for Keith's murder to justice will not stop. I would like to thank the investigation team for their dedication and hard work over a number of years."
Friends and supporters of Nicky Jacobs, who was cleared of murdering PC Keith Blakelock, said the Crown Prosecution Service and Director of Public Prosecutions had questions to answer on why such a "farcical" case came to trial.
Stafford Scott, the co-ordinator of the Tottenham Rights group and one of Mr Jacobs' most vocal supporters, told reporters outside the Old Bailey, "It is not a day of joy. Everybody should be able to take the notion of receiving justice as standard."
Referring to the Blakelock family, Mr Scott added: "This must have been terrible for the family. They have been conned by the Metropolitan Police Service who said this would bring justice."
Winston Silcott, who was found guilty at the Old Bailey of murdering PC Blakelock in 1987 before his conviction was quashed in 1991, claimed the police had brought the case because they were "bitter about what happened".
The family of Pc Keith Blakelock said they were "extremely sad and disappointed at the verdict" following the acquittal of Nicky Jacobs.
A jury took just six hours to clear the 45-year-old of the murder of Mr Blakelock who was stabbed over 40 times in an attack at Broadwater Farm in 1985.
"We are obviously extremely sad and disappointed at the verdict. We viewed this trial as an opportunity to see some form of justice served for Keith," a statement on behalf of the family said.
"There were many people involved in a murder on that night of 6 October 1985 and it is regretful that no-one has yet to be found guilty despite the number of people with knowledge of the events of that night."
The family, who thanked everyone involved in ensuring the case was brought before a jury, said they hoped more people would come forward to bring those responsible to justice.
The Crown Prosecution Service (CPS) has insisted "it was right" to bring a case against Nicky Jacobs over the murder of PC Keith Blakelock.
Jenny Hopkins, deputy chief crown prosecutor for CPS London, said: "This case was charged under the Full Code Test of the Code for Crown Prosecutors following a review of the material from all three police investigations spanning over 20 years.
"Following this review we concluded that there was sufficient evidence for a realistic prospect of conviction and it was in the public interest to charge Nicholas Jacobs with the murder of PC Keith Blakelock.
"It was right that all the evidence in this case was put before a jury and we respect their decision."