A company owned by Prince George's godfather has been ordered to pay damages to a millionaire neighbour after pimps and sex workers invaded an upmarket street.
Hugh Grosvenor, the seventh Duke of Westminster, owns Grosvenor West End Properties which is responsible for a block of flats in Mayfair, London.
Lawyer Peter Clifford, 62, sued his business over "nuisance" caused by visitors - including sex workers and their clients - at the flats next door to his £4.4million three-bedroom mews house.
He said his life has been blighted by "seedy" goings-on, loud parties and "unwanted Airbnb holidaymakers".
Mr Clifford claimed the duke's company didn't do enough to stamp out the anti-social behaviour, which was out of keeping with the otherwise "high-class" Bourdon Street.
Now, following a trial at Central London County Court, a judge has backed Mr Clifford's claims that the duke's company did not take "reasonable steps" quickly enough to try and resolve the problem.
Judge Mark Raeside KC ordered the company to pay Mr Clifford £13,200 in compensation, but rejected a claim to a much bigger payment after finding that the problems were "transitory" and not permanent enough to affect the value of his house.
Mr Grosvenor was told to pay Mr Clifford £12,600 in compensation for having to vacate his master bedroom due to the disturbances.
And he awarded another £600 in general damages for his distress and loss of amenity.
Outlining the case during the trial, Mr Clifford's barrister Tiffany Scott KC said Bourdon Street had been described by estate agents as "one of the most prestigious" addresses in Mayfair and a "centre for contemporary art."
As well as owning the Bloomfield Court block of 12 flats, Grosvenor is also the freeholder of Mr Clifford's leasehold mews house next door in the "quiet" residential street, where he moved in 2003.
Ms Scott said anti-social activities had been linked to the block over the years which were "inconsistent with the quiet and high-class residential character of the area."
They included drug dealing, prostitution, unauthorised short-term lettings to "unwanted Airbnb holidaymakers," loud parties and even threats of physical violence to neighbouring residents.
And she claimed Grosvenor had not done enough to tackle the problems.
"The defendant has taken no measures to stop a very regular stream of people from entering the building, despite knowing that they are visiting either to occupy the flats on prohibited short-term holiday lets or else for the purposes of drug-taking, partying, prostitution or other nuisance-causing activities," she said.
"The defendant allows them up the entrance steps, into the courtyard, into the building, into the lift, and through the corridors.
"The people about whose behaviour the claimant complains, as well as the problematic behaviour itself, are emanating from the common parts of the building."
Giving evidence, Mr Clifford said he had seen men going into the block with prostitutes, drug deals taking place in public and drunk people "totally out of control."
Things got so bad that his master bedroom was rendered "uninhabitable" by the noise outside, with a "pimp" once stood just three metres away from his window, he said.
He had to install CCTV cameras to deter bad behaviour and had retreated from the master bedroom at the front of his house due to the disturbances outside Bloomfield Court.
"This particular block is perfect for organised crime," he told the judge.
"It has no 24-hour concierge. It is the type of property that is targeted for exactly the kind of nuisance we received."
For Grosvenor, barrister Thomas Braithwaite said the worst of Mr Clifford's complaints had reached a "nadir" in 2020 and 2021 but that things had been much improved after the cameras were installed in October last year.
He denied that the company had not taken "reasonable steps" to ensure Mr Clifford's "quiet enjoyment" of his home was not interfered with by "nuisance" from next door.
The case was heard in a four-day trial by Judge Raeside and he has now ruled in Mr Clifford's favour, saying there is no doubt but that the three main allegations - prostitution, loud parties and unlawful short-term letting - had occurred.
"It's impossible, given the wealth of evidence, to come to any other view than that all three took place at times between March 2018 and January 2021," he said.
"It is quite clear Grosvenor knew about these matters over that three-year period."
He said Grosvenor had taken steps to try to eradicate the nuisance and that, following the installation of CCTV cameras last year, the type of nuisance suffered was "radically different" to the serious complaints of crime earlier.
But firm steps should have been taken sooner, which would have helped reduce the level of nuisance Mr Clifford was subjected to, he continued.
An "obvious step" - now being considered by Grosvenor - would have been to introduce a key fob system to keep out those "with no right to enter those flats," he said.
"There were generally further steps, which have proven successful, that could and should have been taken earlier by Grosvenor to abate this nuisance," he said.
A further hearing will take place in the coming weeks to decide who has to pay the substantial legal costs of the case and whether Grosvenor should be forced by court order to take any particular steps to eradicate further nuisance at the block.