Cameramen in the air were able to zoom in on officers through the windows as they searched through belongings. Sir Cliff, who vigorously denies any wrongdoing and has not been arrested, was in Portugal at the time.
"No citizen should have to watch on live television their home being raided in this way," concluded a blistering Home Affairs Select Committee report.
Sir Cliff's lawyer Gideon Benaim denounced the "premature and disproportionate' reporting which caused the veteran entertainment "immeasurable harm".
Friends say Sir Cliff is now determined to launch a concerted fightback. As his association with the BBC goes back to the start of his career - he appeared on Juke Box Jury in 1961 and on the first episode of Top Of The Pops in 1964 - legal action is likely to cause acute embarrassment.
The singer was said to be dismayed to learn of the extent of co-operation between South Yorkshire Police and the BBC in the weeks leading up to the raid.
As the Home Affairs Select Committee noted last month, not only did the force give the broadcaster the date of the search, it also 'handed over a great deal of information freely".
This newspaper can disclose that emails, text messages and other documents given to the committee show that the BBC:
• Expressed concern that the alleged sex abuse victim might ruin its exclusive story by alerting other media.
• Was privy to operational details not usually released to journalists - including how officers struggled to find Sir Cliff's home and how they were considering searching his overseas properties.
• Received a running commentary from police at the start of the raid. At one point BBC reporter Dan Johnson was told: "Going in now, Dan... We have managed to gain entry."
• Asked to be alerted before officers removed anything "so we can get the chopper in place for a shot".
One legal expert said last night that the level of intrusion meant Sir Cliff would have a "strong case" and added that the BBC would struggle to mount a public interest defence.
The police investigation began when a man, now in his 40s, came forward earlier this year to claim Sir Cliff sexually assaulted him during a Christian rally in Sheffield organised by Billy Graham, the American evangelist, in 1985.
The BBC's Johnson first contacted South Yorkshire Police about the allegation in mid-July and spoke to Carrie Goodwin, head of corporate communications.
In a letter, Goodwin recalled that Johnson was able to "detail the allegation, accurately and the location the allegation related to.
"Specifically he spoke about a boy aged between 11 and 14 alleging that he had been taken to a room... where he was made to carry out a sexual act."
A month before the raid, Goodwin sent Johnson an email asking if he would like her to "set something up with the officer in the celebrity case". He replies: "That would be fab."
Notes from the meeting show that Johnson asked if the BBC could accompany officers during the search of Sir Cliff's home. Unsurprisingly, the request was turned down.
However, fearing Johnson was about to break the story prematurely, police felt they had no choice but to deal with him and agreed to give him advance notice of the raid.
In fact the head of the investigation, Detective Superintendent Matt Fenwick would later say the force had been "effectively blackmailed".
Over the next few weeks, dozens of emails and texts were exchanged between the force and the reporter.
In one email, on July 18, Johnson asked if the BBC could speak to the alleged victim. He said he was worried the alleged victim might tip off other media about the raid.
He asked Goodwin: "I don't know how closely you're keeping him updated on progress and plans. I wouldn't want him becoming aware of progress through our interest, prompting him to...alert other media".
Goodwin responded that the "complainant is being kept up to date to an extent but I'll make the team aware of your concerns".
At this point she warns Johnson that the inquiry isn't "progressing as quickly as thought" because "there doesn't seem to be a UK address".
It might mean, she adds, that officers will "need to go and try one of the foreign ones [Cliff owns homes in Portugal and the Bahamas].
"We are considering which one would operationally be the better choice."
Eventually they did find Sir Cliff's Berkshire address, and tipped off Johnson the night before the raid.
Helpfully, one of Goodwin's team sent the reporter an aerial photograph of the property and said: "From what I've been told by officers who are down there now there won't be much to see from the street."
At 10.20am the following day, with the police poised to swoop on the apartment, Johnson exchanged text messages with a police media officer, Lesley Card.
He asked: "You parked underground? Helicopter can't see you".
Card replies: "No we're not parked near the property at this time - while we wait to hear bout entry, we're parked off in the grounds somewhere."
Johnson then asks: "Have you managed to get in his place?".
He is told: "Yes, we have managed to gain entry."
He later asks: "Give me a shout before they take anything out, so we can get the chopper in place for a shot."
When asked about the legal action, a spokesman for Sir Cliff declined to comment.
The singer, who was interviewed under caution by police ten days after the raid, has described the allegation against him as "completely false".
He has received huge support from the public and has continued to work. Next September he will embark on his 75th birthday tour, which has just added a sixth date at London's Royal Albert Hall.
"I am moved by the support the fans have shown, and am very much looking forward to seeing them on the tour next year," he said.
After broadcasting live, the BBC received hundreds of complaints from viewers, with many saying that the coverage made the singer look guilty.
Yesterday, Jack Good, 83, the TV producer credited with turning Sir Cliff into a star in the late 1950s, called the broadcast "shameful".
Sir Michael Parkinson, 79, a former BBC journalist, described it as a "witch-hunt" and attacked the Corporation for an "error of judgment".
Former Shadow Home Secretary David Davis said: "The decision by the leadership of South Yorkshire police to allow the searching of Sir Cliff Richard's house to be televised, like some morally challenged reality TV show, demonstrates there is something sick at the heart of Britain's police and justice system."
However, Home Affairs Select Committee chairman Keith Vaz said the BBC acted "perfectly properly" in its dealings with police over the raid, but the coverage had caused Sir Cliff 'enormous, irreparable damage".
Last night the BBC said the Home Affairs Committee "has already endorsed the way the BBC handled this story. We have nothing further to add".
South Yorkshire Police said: "While we believe our actions in relation to dealing with the media were within policy and were well-intended, they were ultimately flawed and we regret the additional anxiety which was caused to Sir Cliff Richard."
It said it "no longer provides privileged briefings to reporters".
- Daily Mail
