Ruth I. Abrams, the first woman to sit on the highest court in Massachusetts since its founding in 1692, and the author of landmark decisions on family law and gender equality that reverberated nationwide, died on Sept. 12 at a senior residence in Boston. She was 88.

The cause was complications of heart disease, her brother, George S. Abrams, said.

Appointed in 1977, Justice Abrams served on the Supreme Judicial Court, the state’s highest, in Boston for 23 years.

“She had a profound belief that the foundation of our society is equal treatment under the law, and she spent her life putting that into practice,” said Margaret H. Marshall, who followed Justice Abrams as the second woman on the high court (19 years later) and became its first female chief justice.

“But mostly,” added Chief Justice Marshall, who retired from the court in 2010, “her impact was in influencing the number of women and minorities who were appointed to the courts. I would not have thrown my hat into the ring if I hadn’t got a call from Ruth Abrams. She single-handedly changed the face of the Massachusetts judiciary.”