Windsor v. McVeigh was a landmark United States Supreme Court case that dealt with the issue of same-sex marriage. The case was brought by Edith Windsor, a same-sex couple who had been legally married in Canada. Windsor had been denied a federal estate tax exemption for her deceased spouse, Thea Spyer, because the federal government did not recognize same-sex marriages. Windsor sued the government, arguing that the denial of the exemption violated the Equal Protection Clause of the Fourteenth Amendment. The Supreme Court ruled in favor of Windsor, holding that the federal government's refusal to recognize same-sex marriages was unconstitutional. The Court held that the federal government must recognize same-sex marriages in order to provide equal protection to all citizens. The ruling was a major victory for the LGBT community and paved the way for the legalization of same-sex marriage in the United States.

In the case of Windsor v. McVeigh, the Supreme Court was asked to decide whether a contract between two parties could be enforced when one party had died before it was fully performed. The majority opinion held that such contracts were not enforceable and that any rights or obligations under them would die with the deceased party. However, in dissent Justice Field argued that this ruling contradicted established legal principles and precedent which allowed for certain types of contracts to be enforced even after death if they had been partially performed prior to death. He further argued that allowing these kinds of contracts to remain valid would provide greater certainty in business transactions by ensuring both parties are held accountable for their contractual obligations regardless of life events like death or illness.