When Ms. Lyon married her partner of 55 years in 2008, they formed the first legal gay union in California.

In 2004, despite state and federal bans on same-sex marriage, Mayor Gavin Newsom of San Francisco began issuing marriage licenses to same-sex couples. Ms. Lyon and Ms. Martin were the first to receive one, but that union would be short-lived. The California Supreme Court invalidated their marriage a month later, arguing that the mayor had exceeded his legal authority.

Four years later, the same court declared same-sex marriages legal and Mr. Newsom invited the couple back as the first to be married under the new ruling. Ms. Martin died shortly after.

Throughout their 55-year relationship, Ms. Lyon and Ms. Martin were politically engaged. They were among the first lesbians to join the National Organization for Women, and Ms. Martin was later elected to its board of directors. The couple also helped form the Council on Religion and the Homosexual to persuade ministers to accept lesbians and gay men into churches.