The proposal would reverse a 2016 ruling by the labor board that graduate students at private schools are employees - and not merely students. That guidance opened the door to union elections at more than a dozen schools around the country.
Student organizers and union leaders vowed to challenge the rule and continue organization efforts.
"Graduate workers deserve respect for the work they do and the right to join a union, just like any other employee," said Randi Weingarten, president of the American Federation of Teachers. "President Trump doesn't agree - and he's written a new federal rule to try to stop them in their tracks."
The NLRB's position on whether students at private schools have the right to unionize has shifted. In 2004, during the presidency of George W. Bush, a Republican, the board ruled that graduate student instructors are not employees. The board reversed itself in 2016 under President Barack Obama, a Democrat.
"This rulemaking is intended to obtain maximum input on this issue from the public, and then to bring stability to this important area of federal labor law," said NLRB Chairman John Ring, who was nominated by President Donald Trump.
At public universities, unions have represented teaching and research assistants for decades.
The first graduate union at a private school was established at NYU, which voluntarily recognized the union, and since the 2016 ruling, four others have reached contracts with graduate student unions: American University, Brandeis University, The New School and Tufts University. There are also four private universities that are engaged in collective bargaining with graduate unions for a first contract: Harvard, Columbia, Brown and Georgetown, according to William Herbert, director of the National Center for the Study of Collective Bargaining in Higher Education and the Professions at Hunter College.
If the rule change is adopted, it would not prevent private schools from voluntarily recognizing unions, and graduate assistants could also start asserting their right to collective bargaining under state constitutions that cover private institutions, Herbert said.
Universities have generally argued that even though graduate teaching assistants are paid, treating them like employees would disrupt the mentoring relationship between budding scholars and the professors supervising their academic pursuits and research.
Graduate teaching assistants involved in unionization campaigns say collective bargaining is important for them to secure better wages, benefits and a voice in decisions made by university administrators.
Rithika Ramamurthy, a doctoral candidate in English at Brown University, said she and others will press private universities to honor their desire for union recognition, with or without the NLRB.
"Our work is work," Ramamurthy said. "We stand in solidarity with all graduate workers who wish to have a collective voice, and we stand against this proposed rule."
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