A civil union is a legally recognized relationship between members of a same-sex couple, with rights similar to those of a marriage relationship.
In Massachusetts, civil unions are not a legally recognized relationship because the state has legalized same-sex marriage. Massachusetts was the first state in the U.S. to legalize same-sex marriage following the Massachusetts Supreme Judicial Court's decision in Goodridge v. Department of Public Health in 2003. The ruling took effect on May 17, 2004, and since then, same-sex couples have been able to marry, with all the rights and responsibilities of marriage as opposite-sex couples. Therefore, in Massachusetts, same-sex couples are not provided with a separate status of civil union; instead, they have the option to marry, which provides them with the same legal recognition and protections as any married couple would receive.