Former Chief Justice of the Massachusetts Supreme Judical Court Margaret H. Marshall speaks at "Created Equal, Conversations on the American Social Contract: Striving Toward Justice for All" at The John F. Kennedy Presidential Library And Museum on November 9, 2014 in Boston, Massachusetts. (Paul Marotta/Getty)

The judge who legalised equal marriage in Massachusetts in 2003, the first US state to do so, has said that she is thanked by strangers at least once a week.

Margaret Marshall, originally from South Africa, was the first woman and first immigrant to become chief justice of the Massachusetts supreme judicial court in its 328-year history.

In 2003 she wrote the 4 – 3 majority opinion in the Goodridge v. Deptartment of Public Health, which legalised same-sex marriage in the state.

The landmark case was brought by GLBTQ Legal Advocates & Defenders (GLAD), on behalf of seven same-sex couples who had been denied the right to marry, against the Massachusetts Department of Health.

Marshall, who has since retired, wrote in the decision: “Here, the plaintiffs seek only to be married, not to undermine the institution of civil marriage.

“They do not want marriage abolished… Recognizing the right of an individual to marry a person of the same sex will not diminish the validity or dignity of opposite-sex marriage, any more than recognizing the right of an individual to marry a person of a different race devalues the marriage of a person who marries someone of her own race.

“If anything, extending civil marriage to same-sex couples reinforces the importance of marriage to individuals and communities.

“That same-sex couples are willing to embrace marriage’s solemn obligations of exclusivity, mutual support, and commitment to one another is a testament to the enduring place of marriage in our laws and in the human spirit.”

The ruling received a huge amount of backlash, with religious Conservatives desperately trying to delay or reverse it, but on May 17, 2004, the first marriage licenses were issued to same-sex couples.

By 2010, five more states had followed suit and in 2015 the US Supreme Court made equal marriage legal for the entire country.

Speaking at Duke University School of Law, the 75-year-old said: “Goodridge was in November 2003. There has not been one week, anywhere in the world, where someone hasn’t come up to me and said: ‘Thank you.'”

In an interview with NPR in 2014, Marshall said: “Massachusetts is one small part of the United States. It never occurred to me that this would be, in any sense, a groundbreaking decision.”