By james art The 69-year-old veteran MP was stabbed to death by Ali Harby Ali, then 26, at Belfairs Methodist Church in Leigh-on-Sea in Essex in October 2021.
Katie Ames, 39, said she was told Ali was reported to Prevent in 2014, but after one meeting his case was not followed up by the anti-radicalisation program “due to an admin error”.
She told the Sunday Times: “They were reporting on him. People were trying to help us and then why was he allowed to just go on and do whatever he wanted for seven years?
“What happened to my father shouldn’t have been the administrator’s fault.”
Father-of-five Sir David was running an operation in his Southend West constituency when he was attacked by Ali, who was jailed for life in 2022 for the murder.
In an interview with the Sunday Times, Ms Ames, an actress who lives in West Hollywood in the United States, said the pain of his death was “unbearable” and “indescribable”.
She added: “It’s pretty obvious that Prevent is not fit for purpose, it fails people all the time.
“You failed me. It has failed my family catastrophically, it has failed society and it has also failed other Members of Parliament.
The Sunday Times reported that according to a coroner’s report published in July, Prevent’s six-month review of Ali’s case was “missed” and a 12-month review revealed “nothing of concern”.
Ms Ames said there had never been a “full public inquiry into the events leading up to his death” after the coroner concluded the criminal trial was sufficient.
She added: “The people who could actually help me are nowhere to be seen, I feel like we’ve been completely ignored.
“My dad would be so shocked if he knew what we’re going through – he’d be ashamed.”
It was reported earlier this year that Ms Ames had taken legal action against Essex Police and the Home Office by bringing a personal injury claim in the High Court as lawyers said she wanted to “ensure appropriate accountability and learning” from killing his father.
A Home Office spokesman said: “Our thoughts continue to be with the family and friends of Sir David Ames.
“The attack on Sir David Ames was a terrible tragedy, the safety of Members of Parliament is paramount and considerable work has been done in response to his tragic murder.
“Prevention is a vital tool to stop people becoming terrorists or supporting terrorism and addresses all the ideological causes of terrorism.”
A spokesman for Essex Police said: “Sir David Ames was a thoroughly dedicated public servant who worked tirelessly for his community.
“In the immediate aftermath of his murder, two of our heroic unarmed officers ran into the face of danger in a desperate attempt to save him and, of course, apprehended his killer.”
The force added: “We are aware that a protected claim form has been lodged with the court but as these documents have not been served on our force we cannot comment further on them.
“We remain committed to supporting our elected members across the constituency in fulfilling their public duty and to this end we regularly review and advise on security measures for our Members of Parliament.”
Essex Police said that “as with all forces up and down the country”, it does not provide officers to police district surgeries.
Essex Coroners’ Office has been approached for comment.