American gay rights activist Edith Windsor

Edith Windsor, who brought a landmark case to the US Supreme Court that paved a path towards legalising same-sex marriage, has died.

Windsor died aged 88 in New York, said her lawyer, Roberta Kaplan. The cause of death was not given, but Windsor had struggled with heart issues for years.

Windsor became a gay rights pioneer after her first spouse, Thea Spyer, died in 2009. The women had married legally in Canada in 2007.

At 81, Windsor sued the federal government, saying its definition of marriage as a relationship between a man and a woman prevented her from getting a marital deduction on Spyer’s estate.

That meant she faced a huge tax bill that heterosexual couples would not have. The US Supreme Court ruled 5-4 in June 2013 that the provision in the federal Defense of Marriage Act was unconstitutional, and that legally married same-sex couples are entitled to the same federal benefits heterosexual couples receive.