Michael Boudin’s father was a prominent civil rights lawyer who vigorously defended left-wing activists during the McCarthy and Vietnam era. His sister was a ’60s radical in the Weather Underground who pleaded guilty to murder in a 1981 armored car holdup in which two policemen and a guard were killed.
But Boudin, a federal appeals judge who wrote the unanimous decision that declared the Defense of Marriage Act unconstitutional, charted a centrist course and became a jurist known for a moderate temperament, evenhandedness, and independent mind.
“He carved a path of his own,’’ said Nancy Gertner, a former US district judge now at Harvard Law School.
In Thursday’s ruling, the US Appeals Court in Boston held that the federal law, which defines marriage as a union of a man and a woman, unjustly denies government benefits to married same-sex couples.
Boudin, who was nominated to the bench by President George H.W. Bush in 1990, wrote that the court did not overturn the act of Congress lightly, calling it an “unwelcome responsibility’’ for federal judges.
That admission showed his respect for the principle of judicial restraint and the legal complexity of the issues before the court, colleagues said. Michael B. Keating, a Boston lawyer who knows Boudin, said that the decision cited “icons of the law’’ who forged a tradition of judicial deference.
But critics of the decision said the court was guilty of overreaching and called the ruling a “denigration of our federalist system and its time-tested reliability.’’
“This court has the audacity to hold the federal government hostage and force all Americans to recognize a radical social experiment from Massachusetts,’’ said Kris Mineau, president of the Massachusetts Family Institute, which opposes gay marriage.
Born in 1939 in New York City, Boudin graduated from Harvard University in 1961, then Harvard Law School three years later.
From 1987 to 1990, he served as deputy assistant attorney general in the Justice Department’s antitrust division.
That Boudin, appointed by a Republican and known as a centrist, would find the law unconstitutional shows how markedly the legal landscape around gay marriage had shifted in recent years, legal analysts said.
Gertner predicted that the Supreme Court would agree with the ruling. “It’s not surprising that a moderate judge would have ruled this way, given the way the law has gone,’’ she said. “If it’s one area we’ve reserved to the states, it’s the definition of marriage. This is an issue whose time has come.’’Peter Schworm can be reached at email@example.com. Follow him on Twitter @globepete.