Anti-terrorism officers gave the killer who would go on to brutally murder MP Sir David Amess the all-clear due to an admin error, it has emerged.
The shocking revelation has been detailed by the late Amesss daughter Katie who tells of how police did not follow up on killer Ali Harbi Ali due to a missed review of his case.
Sir David was elected Conservative MP for Basildon in 1983 and then served as MP for the Southend West constituency from 1997.
But his tenure was tragically cut short in October 2021 at the age of 69 after Ali fatally stabbed him at Belfairs Methodist Church Hall in his constituency surgery in Leigh-on-Sea for reasons the police described as Islamist extremism.
Now, Katie Amess, who is 39 and an actress, has spoken out about the unbearable pain and questioned how was a terrorist free to kill my dad?.
Sir David was stabbed to death while meeting constituents at Belfairs Methodist Church in Leigh-on-Sea, Essex, on October 15 2021
Sir David Amess was a popular longstanding MP dressed as a knight to celebrate his knighthood in 2015 (right)
The distraught daughter of David Amess has broken her silence on their familys unbearable pain after he was murdered by a terrorist. Pictured Katie Amess now 39
His killer, Ali Harbi Ali, was found guilty of murder and handed a whole-life prison term at the Old Bailey in 2022
The second of Amesss five children, she told the Sunday Times: None of this seems real to me. Its just still so hard to accept this has happened.
The police told us they didnt follow up with him (Ali) due to an admin error.
He was reported. People were trying to help us. And so why was he allowed to just go on and do whatever he wanted for seven years? What happened to my dad should not have been an admin error.
Katies despair comes after Ali was visited by a Prevent officer in January 2015 when he was 18 - the first of two intended meetings.
Speaking at the murder trial, Ali later said: I just knew to nod my head and say yes and they would leave me alone afterwards, and they did.
The second intended meeting did not happen and his case was closed in 2016, after which all involvement with police ceased.
Katie added there had never been a full public examination into the events leading up to his death, after a coroner concluded that the criminal trial had been sufficient.
Andrew Rosindell (left) with members of the music man project unveil a statue of murdered MP Sir David Amess on Chalkwell seafront, in Southend
David Amess and wife Julia, with their fourth child, baby daughter Alexandra. They are pictured with two of their other children, David and Katie
She said: The people that actually could have helped me are nowhere to be seen, it feels like we have been completely disregarded.
My father would be so shocked if he knew what we were going through - he would be ashamed.
Its pretty obvious that Prevent isnt fit for purpose, it has consistently failed people.
It failed me. It failed my family catastrophically, it failed the public and also it failed other Members of Parliament.
It was reported earlier this year that Ms Amess had taken legal action against Essex Police and the Home Office by filing a personal injury claim at the High Court, as lawyers said she wanted to ensure proper accountability and learning from her fathers murder.
Lincoln Brookes, senior coroner for Essex, said there had been some shortcomings in the programme, adding: Ultimately the [Prevent] case was closed with the issues the perpetrator had not being addressed.
Sir David pictured outside his surgery in 2021
Ali, a British citizen and son of a former media adviser to a prime minister of Somalia, repeatedly stabbed Amess in the 2021 attack for what he said was revenge for the lawmakers support for airstrikes on Syria
However, he concluded that the attack may not have necessarily been prevented had the programme continued: It would be speculative to assume that national security services do, should or could, detect and track every Islamic State sympathiser.
A Home Office spokesman said: Our thoughts continue to be with Sir David Amess family and friends.
The attack on Sir David Amess was an awful tragedy, the safety of members of Parliament is paramount, and significant work has been taken forward in response to his tragic killing.
Prevent is a vital tool to stop people from becoming terrorists or supporting terrorism and tackles all ideological causes of terrorism.
Ali Harbi Ali was found guilty of murder and handed a whole-life prison term at the Old Bailey in 2022.
He had told the trial he had no regrets about the murder, defending his actions by saying Sir David deserved to die because he had voted in Parliament for air strikes on Syria in 2014 and 2015.
Sir David was knighted for services to political and public service in 2015 and has been described by friends and family as someone who put the wellbeing of his constituents above personal ambition and worked all hours championing causes he felt to be right.