A Swiss criminal court on Friday sentenced four members of the wealthy Hinduja family with between four and 4 1/2 years in prison for exploiting their vulnerable domestic workers. The court at the same time threw out the more severe charges of human trafficking.

The four — Indian-born tycoon Prakash Hinduja and his wife, son and daughter-in-law — were accused of trafficking of their servants, mostly illiterate Indians, who were employed at their luxurious lakeside villa in Geneva.

The four were not in court in Geneva though a fifth defendant — Najib Ziazi, the family’s business manager — was in attendance. He received an 18 months suspended sentence.

The lawyers representing the defendants said they would appeal.

The court said the four were guilty of exploiting workers and providing unauthorized employment. It dismissed the trafficking charges on the grounds that the staff understood what they were getting into.

The four Hinduja family members were accused of seizing workers’ passports, paying them in rupees – not Swiss francs — barring them from leaving the villa and forcing them to work excruciatingly long hours for a pittance in Switzerland, among other things.

Last week, it emerged in criminal court that the family — which has roots in India — had reached an undisclosed settlement with the plaintiffs. Geneva prosecutors opened the case for alleged illegal activity including exploitation, human trafficking and violation of Swiss labor laws.

The family set up residence in Switzerland decades ago, and Prakash was already convicted in 2007 on similar, if lesser charges, though prosecutors say he persisted in employing people without proper paperwork anyway.

Swiss authorities have already seized diamonds, rubies, a platinum necklace and other jewelry and assets from the family in anticipation that they could be used to pay for legal fees and possible penalties.

Prosecutors said that at times the staffers — in jobs like cooks or house help — were forced to work up to 18 hours a day with little or no vacation time off and for pay that was equal to less than one-tenth of the comparable amount required under Swiss law.

Employees worked even later hours for receptions and slept in the basement of the villa in the upscale Cologny neighborhood — sometimes on a mattress on the floor, prosecutors said. They described a “climate of fear” instituted by Kamal Hinduja.

Some employees allegedly spoke only Hindi and were paid their wages in Indian rupees in banks back home that they couldn’t access.

A separate tax case brought by Swiss authorities is pending against Prakash Hinduja, who obtained Swiss citizenship in 2000.

Along with three brothers, he is a leader of an industrial conglomerate in sectors including information technology, media, power, real estate and health care. Forbes magazine currently puts the net worth of the Hinduja family at some $20 billion.