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An Indian man has won a landmark court battle to be proved the illegitimate son of a leading politician. In a society where many children born out of wedlock are disowned by fathers, it's thought the case could open the floodgates for many similar claims.

Thirty-five-year-old Rohit Shekhar stands proud, with an air of vindication. He wears a pristine white shirt and the surroundings of his home in posh South Delhi bear the hallmarks of upper-middle-class living.

He smiles and says: "I must be one of the first in the world to fight to be proven a bastard."

For seven years he fought a paternity suit against one of India's most powerful politicians - 88-year-old Narayan Dutt Tiwari, who has held numerous cabinet posts for the Congress Party in a political career spanning six decades. The word "bastard" was frequently used in court, he says.

"This patriarchal system in India doesn't accept me or my mother," he says.

"This discrimination becomes even more severe and much uglier when you leave the rich urban areas and move to the hinterland."

Many Indian politicians are known to have enjoyed long-standing extramarital affairs but this is generally not discussed in the open and the Indian media mostly refrain from exposing them.

It's also extremely rare for the woman to publicly admit an affair or having a child out of wedlock.

So Shekhar's paternity suit caused a sensation.

When he was a child, a powerful man would often visit his mother in the house where they lived with his grandparents.

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Every visit was accompanied by numerous security people, fleets of big cars and lots of hushed conversations behind closed doors. He overheard conversations filled with tears and screams and he remembers his mother falling sick regularly and being rushed to hospital for medical care.

The idea of my father not accepting me publicly was terrible Rohit Shekhar

Shekhar also remembers that this "big man" used to visit him on his birthdays and he often wondered why he didn't do the same for his elder brother.

At a certain point he started asking questions, and the secret was finally revealed to him by his grandmother when he was about 15 years old.

His mother, Ujjawala Sharma, had left her husband's home with a two-year-old son, Rohit's elder brother, in the mid-1970s. She went back to live in the house belonging to her father, the prominent politician Prof Sher Singh. It was then that she started seeing ND Tiwari who was an up-and-coming politician at that time and a family friend.

After few years of courtship, she gave birth to Rohit, but ND Tiwari refused to lend his name to the child. Shekhar says it would have been a big blow to Tiwari's political career, as he was a married man.

So Shekhar's birth certificate carried his mother's husband's name - BP Sharma.

"Once I got to know the truth, I felt angry and humiliated," he says.

"The idea of my father not accepting me publicly was terrible. I was confused over why my mother was not given the status she deserved. I always felt we were viewed as a joke in the extended family. I could not take it."

It was his anger that led him to fight to be recognised for who he was and where he came from.

In a conservative country like India where marriage and family are vital for social respectability, the stigma of being illegitimate is profound. The verdict of this case, he feels - and the DNA test that Tiwari was obliged to undertake - has set a new precedent.

Image copyright Getty Images Image caption Rohit Shekhar with his mother Ujjawala Sharma outside the High Court in Delhi

Vedanta Verma, the young lawyer who argued Rohit's case, says many people have since approached him for advice on paternity suits. And there are tens of thousands of women who may now seek DNA tests to prove paternity, he estimates.

Verma also sees a threat to the "presumption of legitimacy", enshrined in a law dating from 1872, which presumes that a child born to a married woman is her husband's, unless it can be demonstrated that the couple were not in the same place at the time of conception.

India is still a feudal society and a very unforgiving place for women and children Rohit Shekhar

"This is an archaic law framed by the Britishers but now it doesn't reflect the modern realities of Indian society so it must change," says Verma, who points out that it no longer exists in any other Commonwealth country.

Shekhar has not sought any financial compensation from his father, even though his case has taken a lot of his time and energy.

When he began his suit seven years ago, the stress caused him to suffer a heart attack he says. He also had a stroke, which left him with a limp.

The success of his suit had one completely unexpected result - two weeks ago Tiwari, a widower for many years, married Shekhar's mother.

"I didn't go to the wedding. I feel happy for my mother and marrying at this stage is also something which will set new examples in Indian society," says Shekhar.

He now says he has a new battle to fight - to get certain words banned from being used in the courts.

"No child can be illegitimate, it's only a father that can be illegitimate!" he states firmly.

He wants to file a petition to stop children being referred to as "bastards" by lawyers and judges, as he was.

He also takes issue with words like "concubine" and "unchaste", which are often used when referring to a woman who is not in a married relationship.

"India is still a feudal society and a very unforgiving place for women and children," he says. "I want it to change."

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