The Hindujas are worth £37bn and their London home has 30 bedrooms, yet four of them face jail for paying Indian servants £6.19-a-DAY: GUY ADAMS on the shameful cruelty of the UK's richest family

Early one morning, police cars sweep along the shore of Lake Geneva to an exclusive suburb named Cologny, where they turn right, climb a few steep residential streets, and grind to a halt outside one of the neighbourhood's many imposing sets of security gates.

It's 2018, and officers are raiding a large but strangely charmless hillside mega-mansion that sits on a corner plot boasting views that stretch from the local yacht club to the Jura Mountains. 

Protected by tall concrete walls, topped with impenetrable 30 ft hedges that protect the privacy of bathers around its vast swimming pool, this sprawling complex is home to one Prakash Hinduja and his wife, Kamal.

The elderly businessman is patriarch of the Swiss offshoot of Britain's wealthiest family, the Hindujas. And he's about to have a very bad day indeed. 

Police, apparently acting on a tip-off, are simultaneously raiding the offices of a local bank, as well as several other nearby companies that belong to the sprawling global empire controlled by Prakash and his three brothers.

Over the ensuing hours they will seize a huge cache of computer hard drives, along with box after box of documents relating to the domestic affairs of Prakash and his son Ajay, who is also based in the family's Swiss compound.

Eventually, detectives will lay claim to a total of 2.7 million items of evidence implicating the duo, and their wives, in a grotesque scandal involving the criminal exploitation of domestic staff that father and son — along with their spouses — employ to cook, clean, nanny children, and carry out other menial tasks that allow billionaires to live in the style to which they are accustomed.

Singing like cuckoo clocks, as they prepared for a case that finally came to court this month, were three of their victims.

A 43-page indictment, shared during proceedings, told how the Hindujas, whose family is worth an estimated £37 billion, subjected their staff to Dickensian employment practices, treating them like indentured servants in a contemptible display of avarice and tight-fistedness.

These poor, mostly-illiterate workers had been recruited in India and shipped to Europe on tourist visas. 

Sleeping in a windowless basement, sometimes on mattresses laid on the floor, they were then paid as little as £250-a-month to work seven days a week, 15-18 hours a day, for years on end.

That works out as about a tenth of Switzerland's minimum wage.

At one jaw-dropping moment during the two-week trial, which kicked off earlier this month, prosecutor Yves Bertossa explained how one Hinduja employee earned a mere seven Swiss francs [£6.19] per 18-hour day. 

He then showed the court a budget document titled 'Pets', which revealed that the family was simultaneously spending 8,584 francs [£7,616] per year on its pet dog. 'They spent more for one dog than one of their servants,' he declared.

Proceedings culminated on Friday night at the Palais de Justice in Geneva, where Prakash, 78, and wife Kamal, 75, were convicted of exploiting staff and providing unauthorised employment and sentenced to four-and-a-half years in prison. 

Their son Ajay, who is 56, and his wife Namrata, 50, got four years. A fifth defendant, the family's business manager Najib Ziazi, was handed an 18-month suspended sentence.

The outcome was nothing if not richly deserved, if only half of the allegations aired in the indictment are true. 

It told how staff were driven directly to the family's compound upon arrival in Geneva, before having their passports confiscated by the family's elderly matriarch Kamal, who was accused of overseeing a 'climate of fear' at the property.

Employees were banned from leaving the premises without her permission, and paid their pitiful salaries in rupees, transferred to banks in India that they were unable to access from Europe

'They could not, by force of circumstances, leave the property, having no knowledge of the city, the environment of the villa and no financial or personal resources in Geneva,' reads the indictment.

'Likewise, Kamal Hinduja often told them that if they went out, they could be arrested by the police and sent back to India, which terrified them.'

'They were paid for their work in India, meaning they had no Swiss money and therefore limited freedom in the country.'

Some of the only times the victims could escape from the property came when they joined the retinue of staff who travelled with the Hindujas to their other luxury properties, which included a ski chalet in the Swiss alps and villa on the Cote d'Azur. 

But as prosecutor Bertossa told court, this wasn't exactly a holiday. 'What were they [the servants] doing there?' he asked in court. 'Jetskiiing?'

In what Bertossa characterised as evidence of a conspiracy to cover up the whole thing, no official Swiss paperwork was used to document their employment.

Instead, the family used short-term Schengen visas to allow the Indian nationals entry, which they renewed over and over again. 

The prosecutor said this was an effort to hoodwink the authorities. Astonishingly, their appalling treatment of staff was part of a pattern of unlawful behaviour that had been going on for two decades, the court heard.

Exploitation of staff had, in fact, been the subject of a previous employment tribunal that in 2006 saw Ajay questioned by police, while Prakash and Kamal were convicted of minor infractions. 

Yet rather than mend their ways, the ultra-wealthy family appears to have carried on regardless.

As the more recent police investigation progressed, the Hinduja clan's thoughts quickly turned to reputation management.

Draconian European privacy laws were initially used to prevent local newspapers from reporting on police raids, while a compensation case brought by the three alleged victims was vigorously contested for almost six years, before being settled days after reports of this month's court case began to emerge. 

Despite that move, Swiss prosecutors chose to continue with the criminal case due to what they described as the gravity of the lawbreaking.

In court, an army of highly paid lawyers sought to downplay the extent of their clients' criminality. Ajay's lawyer, Yael Hayat, argued that salaries alone didn't reflect the real pay of servants, since they were also provided with board and lodgings.

It 'can't simply be reduced to what they were paid in cash', she said, adding that talk of 18-hour days was an exaggeration because 'when they sit down to watch a movie with the kids, can that be considered work? I think not.'

In another charming aside, a different lawyer, Robert Assael, said workers were 'grateful to the Hindujas for offering them a better life'. A third, Nicolas Jeandin, said 'we are not dealing with mistreated slaves'.

The panel of judges who presided over the case agreed, up to a point: although the four Hindujas were convicted of exploitative employment practices, they were found not guilty of people trafficking on the grounds that their staff knew the financial terms of their employment when they had signed contracts in India.

Sentencing, Judge Sabina Mascotto said: 'They were exploited given their situation in India was so precarious and they were exploited as they didn't know the language, had their passports confiscated and were only ever paid every three to six months.

'The four Hindujas knew the vulnerabilities of the staff and knew what the rules were in Switzerland, as they all were Swiss citizens and Ajay was educated in Switzerland.'

In addition to the prison sentences, she ordered the family to pay 850,000 Swiss francs (£750,000) in compensation and 270,000 francs (£240,000) in legal fees.

The criminal convictions are just the latest in a series of mucky scandals to hit a family whose name has in recent decades become a byword for stratospheric wealth.

Their tale begins with Prakash's father, Parmanand Hinduja, a trader from Bombay who became rich exporting oil, cement and fertilisers to the Shah's Iran before handing over to his four sons. 

After the 1979 Iran revolution, the family moved its centre of gravity to London, making canny investments in the oil trade which elevated them to billionaire status.

Parmanand died in the mid-1970s and, ever since, the empire had been jointly shared by his four sons: Prakash, his elder brothers Srichand and Gopichand, who settled in London, and a younger sibling named Ashok.

Operating as what PR men dubbed a sort of 'Fab Four' of the global business elite, they presented a united front, often wearing matching suits and round glasses, and talked of achieving success via a unique Three Musketeers-style family code where 'everything belongs to everyone and nothing belongs to anyone'.

The brothers even shared ownership of various homes. Their 18th-century residence in London's Carlton House Terrace, near Buckingham Palace, is made up of four interconnected six-storey buildings, boasts 30 bedrooms, and is worth upwards of £250 million.

They also own the Raffles Hotel, on the site of the Old War Office on London's Whitehall, where suites can set you back £25,000-a-night. It's a jewel in the crown of a corporate empire operating in nearly 40 countries, employing almost 200,000 people.

Extreme wealth has brought lofty connections, including friendships with Prime Ministers Thatcher, Blair and Major and Presidents Reagan, Bush and Clinton. 

They met Princess Anne and the late Queen attended Diwali celebrations at their London home, while the King sent congratulatory messages to Hinduja weddings, at which 16,000-strong guest-lists have been entertained by Bollywood stars, along with such luminaries as singers Jennifer Lopez and Nicole Scherzinger.

Yet just as money hasn't exactly made Prakash the most generous of employers, it has also not always brought the family happiness. Indeed, over the years, the Hinduja clan has occasionally found itself at the centre of scandal.

In 1992, Srichand's son Dharam killed himself in a family feud over an arranged marriage. The 22-year-old, who was educated at Westminster School, fell in love with an Anglo-Indian who was a Roman Catholic from Australia.

The family, who wanted him to marry a high-caste Indian woman, disapproved. When the young couple fled to Mauritius, having tied the knot at Chelsea Register Office, they put adverts in local newspapers suggesting he was a missing person. 

Torn between his love for his bride and loyalty to the family, and seemingly hearing that they were to be tracked down and forcibly separated, Dharam and his wife made a suicide pact.

After tying his wife to a bed and dousing them both in white spirit, he set himself alight. Mercifully, she managed to escape.

Terribly injured, Dharam was flown to London but could not be saved.

Almost a decade later, in 2001, the Hindujas became embroiled in a political row when Peter Mandelson was forced to resign from the New Labour government amid allegations he had helped secure a British passport for Srichand for a £1 million donation to the 'spirit zone' at the Millennium Dome (a much-criticised official report cleared him of wrongdoing).

More recent years have seen a deeply unedifying family dispute over the all-important question of how the business will be managed once the current generation of patriarchs has died.

In 2022, a leading British judge raised serious concerns about the welfare of Srichand, who was suffering from severe dementia.

Mr Justice Hayden revealed that a family scrap (likened to the battles in the TV series Succession within a warring media business family) over control of the firms had so divided the clan that members were unable to agree where the elderly billionaire ought to be treated or how his medical care should be financed.

This had led to a grotesque situation where, despite what the judge aptly described as 'the extraordinary scope and reach of their financial capacity', Srichand's wealthy relatives had failed to make financial arrangements for him to be properly looked after in a private medical facility. 

The judge had therefore been 'driven to consider' placing one of Britain's wealthiest men in an NHS care home.

After Srichand died, in May last year, the family could have been forgiven for thinking their legal woes were behind them. 

But recent events in Switzerland, where authorities have seized diamonds, rubies, a platinum necklace and other jewellery and assets from the family to cover legal fees and possible penalties, now suggest they may only just starting.

In addition to this month's exploitation trial, a tax case is still pending against Prakash in Switzerland after the country's highest court ruled he could owe Genevan authorities more than 125 million francs in back taxes.

Meanwhile he, Ajay and their respective wives have vowed to appeal against the verdict, which under Swiss law was reached by a panel of three judges (rather than a jury).

That move may at the very least delay them from incarceration, since the country's court system dictates that a judgment is never considered final until all avenues of appeal have been exhausted.

'We're going to fight it to the bitter end,' one of their lawyers said on the steps of the court after the verdict was announced.

'We are appalled and disappointed' read a statement issued over the weekend. 'The family has full faith in the judicial process and remains confident that the truth will prevail.'

Doubtless the truth will indeed prevail. Whether that will be enough to keep this offshoot of Britain's wealthiest family out of prison of course remains to be seen.