New Delhi: In another landmark judgment, the Supreme Court on Thursday decriminalised adultery after striking down a British era law, Section 497 of the Indian Penal Code, terming it as unconstitutional, archaic and manifestly arbitrary, with one judge saying women can't be treated as 'chattel.'

"Mere adultery can't be a criminal offence. Adultery may not be the cause of an unhappy marriage, but other way around. It will tantamount to punishing people who live in an unhappy marriage.

"It is a matter of privacy. Husband is not the master of wife. Women should be treated with equality along with men," Chief Justice Dipak Misra said.

Earlier in September, the apex court had decriminalised same sex offence under Section 377 of the IPC, which was another British era law.

Most countries have abolished adultery as a crime. "It shouldn't be a criminal offence, other people are also involved in it," Misra said, reading out the judgment, on behalf of himself and Justice A M Khanwilkar.

Any discrimination shall invite the wrath of the Constitution, the Chief Justice said, adding that a woman cannot be asked to think about the way society desires her to do.

Justice Rohinton F Nariman, reading out his judgment, said: "Women can't be treated as chattel."

Justice D Y Chandrachud in a concurring but separate judgment said society has two sets of morality in sexual behaviour - one for women and another for men.

Society treating women as embodiment of virtue leads to crime like honour killing, he said, adding that the archaic law was against dignity, liberty and sexual autonomy guaranteed under the Constitution.

Justice Chandrachud said a woman had sexual autonomy within marriage and marriage does not mean ceding autonomy of one to the other.

"Ability to make sexual choices is essential to human liberty. Even within private zones, an individual should be allowed her choice," said Justice Chandrachud. "Women can't be treated unequal participant in the marriage."

Inability to make choices within the marriage by the woman was violative of right to equality and right to life, he added.

Partners in a marriage should have respect for each other's sexual autonomy, he said.

"Society imposes impossible virtues on a woman. Raises her to a pedestal, confines her to spaces," Justice Chandrachud said, adding that women were expected to be pure, but men have no qualms in raping her, assaulting her, committing female foeticide or discriminating against her within their homes.

Describing the adultery law as a gender stereotype, Justice Indu Malhotra, the only woman judge in the Constitution Bench, said there was no justification for the law to continue on the statue book.

The discriminatory adultery law (Section 497 IPC) had punished only a married man for having extramarital sexual relationship with a married woman - a law defended by the Centre as being essential for preserving the institution of marriage.

Section 497 of the IPC had stated: "Whoever has sexual intercourse with a person who is and whom he knows or has reason to believe to be the wife of another man, without the consent or connivance of that man, such sexual intercourse not amounting to the offence of rape, is guilty of the offence of adultery."