A former senior Metropolitan Police officer says he was moved from his post when he revealed plans to investigate politicians over child abuse claims.
Clive Driscoll says his inquiry into 1980s London children's homes was "all too uncomfortable to a lot of people".
He also believes there were "disruption tactics" within the Met during his inquiry that led to the conviction of two of Stephen Lawrence's killers.
The Met defended its murder inquiry and said Lambeth investigations continued.
List of suspects
Mr Driscoll told BBC Newsnight that while conducting a 1998 inquiry into allegations of abuse in children's homes in Lambeth, south London, in the 1980s, he was passed a list of suspects' names, including politicians, that he wanted to investigate.
Speaking for the first time since retirement, he said: "Some of the names were people that were locally working, some people that were, if you like, working nationally.
"There was quite a mix really because it appeared that it was connected to other boroughs and other movement around the country."
He said after he had shared his suspicions at a meeting, he was taken off the investigation.
'Fear of reprisals'
"I certainly, in a case conference, disclosed suspects' names... but I was informed that was inappropriate and I would be removed from my post."
Mr Driscoll added: "Whenever people spoke to you... about what they had seen, it was almost on the proviso that they wouldn't make a statement and that they would be scared if you released who those people were that were talking, for fear of reprisals to both their selves and their families."
He said he felt there had been mistrust on both sides.
"It appeared that certainly people didn't trust the Metropolitan Police Service, and I think the Metropolitan Police Service possibly didn't trust some of the people that it was working with."
Did he fear he was stopped from investigating the Lambeth claims because he suspected more than one politician was involved in child abuse?
He replied: "At the time I just felt that it was all too uncomfortable to a lot of people."
After Mr Driscoll said he was moved, police continued to look at more than 20 children's homes.
Investigations are still ongoing and there have been several convictions.
The Met said it was looking into his claims concerning his removal from the investigation and have called him to a meeting in Scotland Yard on Wednesday.
His claims come as two inquiries into historical child sex abuse allegations have dominated recent national headlines.
One is a sweeping, independent inquiry looking at how public bodies dealt with these types of allegations, while the other will look at how the Home Office handled abuse claims dating from the 1980s.
Meanwhile, Mr Driscoll also told Newsnight that senior officers in the Met had discussions about holding back certain documents from the Ellison Review, the independent inquiry that looked into allegations of police corruption in the Stephen Lawrence case.
He warned: "One bad decision around disclosure undoes the remarkable work that police officers do up and down the country.
"For me, just be open and honest, warts and all."
Stephen Lawrence was 18 when he was stabbed to death near a bus stop in Eltham, south-east London, in April 1993, in a racist attack by a gang of white youths.
After years of legal attempts had failed, Mr Driscoll eventually led an investigation that brought the case to court successfully.
David Norris and Gary Dobson were convicted of murder, in January 2012.
But Mr Driscoll said there had been officers inside the Met who did not want a "successful prosecution".
"There were certainly people I think in senior levels in the Met that weren't enthusiastic about the investigation. I certainly felt that."
He felt so concerned about what he described as "disruption tactics" that he said he emailed senior officers with his fears.
Now he has left the force, he said relationships between the Lawrence family and the Met were as bad as they had been just after Stephen's murder.
'Right the wrongs'
Mr Driscoll supports Metropolitan Police Commissioner Sir Bernard Hogan Howe, but believes the Met must now be as transparent as possible to rebuild the trust of the public.
He said: "I believe we are in a position today where we have an opportunity to learn and we have an opportunity to put right some of the wrongs."
The Met told Newsnight no relevant Stephen Lawrence material had been intentionally withheld and its policy was to be open and transparent.
It added it was still committed to continuing the Lawrence investigation.