A California judge recently ruled in a similar case that teacher tenure laws violate students’ civil rights under the state’s constitution. The group that brought that case, known as Vergara v. California, said it would be pursuing similar litigation elsewhere as well. In a sign of the legal firepower attracted to the cause, Theodore B. Olson, Mr. Boies’ partner in the California same-sex marriage case, has been advising the Vergara plaintiffs.

In an interview in his firm’s offices in Manhattan, Mr. Boies said he viewed the cause of tenure overhaul as “pro-teacher.”

“I think teaching is one of the most important professions that we have in this country,” he said. But, he added, “there can be a tension” between union efforts to protect workers and “what society needs to do, which is to make sure that the social function — in this case teaching — is being fulfilled.” Mr. Boies, who said he viewed education as a civil rights issue, is offering his services pro bono.

This is not Mr. Boies’ first engagement with efforts to overhaul public education. He is on the board of StudentsFirstNY, the New York chapter of the advocacy group led by Michelle A. Rhee, the former schools chancellor in Washington, which also supports teacher evaluations based on test scores and the expansion of charter schools.

Teachers’ unions say the lawsuits against tenure demonize educators and ignore real problems. “The bigger issue is how do you attract and retain great teachers into schools and how do you address the many issues that are created by poverty?” said Randi Weingarten, president of the American Federation of Teachers, the country’s second largest teachers’ union, who called the lawsuits “smoke screens.”