Local 33 and its peer organizations are planning a major demonstration for Commencement Day, as the graduate student union continues to escalate its labor battle with Yale.

In a May 9 email to members of the Connecticut AFL-CIO, Local 35 President Bob Proto — whose union is part of the same umbrella organization, UNITE HERE, as Local 33 — promised to stage a disruptive protest during Commencement, which will be held on May 22.

“On Yale’s most important day, we will flood the city of New Haven with working people, to show that nobody — not Donald Trump, not the Yale administration — will make us move backward now,” Proto wrote.

In another widely circulated email on May 12, Jaime Myers-McPhail, a leader of New Haven Rising, said the city “will become ground zero in the fight for workers under Trump” on Commencement Day. On a Facebook event page, Local 33 is urging students to “stand with us” during Commencement, although the page does not yet include any specific information about the protest.

Local 33 Chair Aaron Greenberg GRD ’18 and union spokeswoman Sarah Eidelson ’12 did not respond to requests for comment. In a statement to the News, Yale spokesman Tom Conroy said the University is “aware of the scheduled demonstration and has made contingency plans to give the graduating students and their families and friends the celebratory day they deserve.”

After winning labor elections in eight academic departments in February, Local 33 demanded that Yale begin the collective bargaining process. But over the past month, the University has refused to open negotiations and is instead appealing the legal underpinning of the union’s departmental elections with the National Labor Relations Board.

Local 33 argues that the University is deliberately stalling as it waits for Trump to nominate anti-union appointees to the NLRB. Last month, eight graduate students began a hunger strike on Beinecke Plaza to pressure Yale to come to the table. And during undergraduate move-out last week, nearly two dozen graduate student protesters were arrested after blocking three downtown intersections during one of the most traffic-heavy days of the year.

But as news of the demonstration spread on social media, graduating seniors expressed anger and sadness about Local 33’s plans to disrupt Commencement. In an interview with the News, Mimi Pham ’17, the treasurer for the class of 2017, said that although she generally supports Local 33, the union’s plans are “a little bit insensitive to the 1,300 graduating students.”

“My peers and myself were really looking forward to Commencement as the culmination of four years of really hard work,” Pham said. “ I understand why they would use Commencement as a day to demonstrate. But I do wish, from just an organizational point of view, that it wouldn’t happen.”

Lily Engbith ’17 — a graduating senior and New Haven resident who supports Local 33 as well as Yale’s other two unions — said the demonstration was unfair to the thousands of family members traveling to campus for Commencement .

“It targets those who have the least to do with their issue with the university administration,” Engbith said. “Given how many families are travelling, I think it’s really inappropriate for them to try to upstage this event.”

Along with the undergraduates, students in Yale’s graduate and professional schools receive diplomas on Commencement Day. In an interview with the News, Elizabeth Mo GRD ’18 — a former president of the Graduate and Professional Students Senate who now runs the anti-Local 33 group GASO — criticized the union’s plans, predicting that many of the protesters will not be Yale students.

“I bet none of those people are going to be graduate students,” Mo told the News. “They’re getting [Locals] 34 and 35, and they’re bringing in outside politicians who get funding from UNITE HERE. This is not going to be representative of grad students.”

The demonstration scheduled for May 22 would not be the first time that a labor conflict has disrupted Commencement. In 1996, thousands of union members from across the northeast staged a “People’s Commencement” outside Old Campus to protest stalled contract negotiations between Yale and the union representing clerical workers, cooks, janitors and researchers, according to The New York Times.

DAVID YAFFE-BELLANY