Teaching and research assistants at Columbia University are striking to protest the school’s refusal to negotiate a contract. (Courtesy Graduate Workers of Columbia-United Automobile Workers.)

Hundreds of teaching and research assistants at Columbia University went on strike Tuesday after more than a year of pleading with the Ivy League school to negotiate a contract.

Graduate student workers began picketing on campus Tuesday morning to protest what they say are unpredictable workloads, late pay, unstable health care benefits and inadequate protections against sexual harassment and assault. The strike, planned to last a week, arrives as professors are wrapping up classes. Many professors rely on graduate students to teach, grade papers and perform research.

“Columbia gives us W2s, they treat us as workers, they need us as workers,” said Rosalie Ray, a doctoral candidate in urban planning and a member of the Graduate Workers of Columbia-United Automobile Workers. “I spend my time . . doing actual teaching.”

Teaching and research assistants at Columbia voted overwhelmingly in December 2016 to join the UAWbut the university filed objections with the National Labor Relations Board. That panel sided with the graduate students last year, but the university announced in January it would not negotiate with the union. Instead, the university said it would plead its case to a federal court of appeals.

“We have long supported unions and collectively bargain with more than a dozen unions representing thousands of university employees. But we believe that student teaching and research assistants who come to Columbia for an education are not employees under the law,” said Caroline Adelman, a Columbia spokeswoman.

University leaders have said the federal courts are best suited to settle the employment status of graduate students because the National Labor Relations Board has reversed its stance several times during the past 15 years.

Columbia provost John H. Coatsworth, in a letter sent last week to the school community, said the university would bargain with the union if the courts determine that students are employees under federal law.

Still, he said recognizing graduate students as employees would be detrimental to the university’s academic mission and the nature of graduate education. Coatsworth said collective bargaining would undermine the autonomy of individual students and university departments because they would be bound by a “one-size-fits all contract.”

The provost sent the letter after the graduate student union voted in favor of a strike earlier this month. The union wrote Columbia president Lee Bollinger last week demanding the university declare its intention to begin bargaining by Tuesday or face a walkout. Columbia informed students last week that classes would not be disrupted by a strike and encouraged them to plan to attend as usual.

“We do not understand why the GWC-UAW prefers the pressure tactics and disruption of a strike to a definitive, nonpartisan resolution of that legal question in the federal courts,” Adelman said.

Union organizer Ray said graduate students have no interest in further delays after nearly two years of waiting for Columbia to come to the bargaining table. The group, she said, has considered filing an unfair labor practice claim, but that would only prolong the process.

“We want a union now,” Ray said. “If we file an unfair labor practice and it goes through the federal courts, it’s just one more way for the university to delay having to bargain with us. The law has been settled. Columbia is just choosing not to follow it.”

Having a bargaining unit to advocate for student workers could make a world of difference in cutting through bureaucracy at Columbia, Ray said. She recalls an incident last semester in which the university took two months to pay teaching assistants in her department. Ray, who works two jobs, said she was able to make ends meet, but some of her colleagues were not.

Adelman said “in the rare and limited instances that a disbursement is delayed, the cause typically is missing or incomplete paperwork submitted by student assistants.”

Ray receives an annual stipend of $28,500 for her work as a teaching assistant, not nearly enough in one of the most expensive cities in the country, she said. The university covers her tuition and provides health care benefits, but Ray said the coverage is limited and taxed.

In his letter last week, Coatsworth said the university has “worked continually for the past decade to increase stipends, enhance benefits and improve the quality of life” for graduate students. He said the average doctoral student receives tuition and other benefits from Columbia totaling about $82,000 a year, though there is variation from one school to the next.

Teaching and research assistants at Columbia have been steadfast in their fight for employment rights. Their campaign to join the UAW in 2014 reignited debates over graduate worker rights at the National Labor Relations Board. At the time, Columbia joined Stanford University, the Massachusetts of Institute of Technology and the rest of the Ivy League in fighting efforts to unionize.

In a legal brief, the schools argued that involving students in the bargaining process would disrupt operations because negotiations could include such core matters as class length, amount of grading or curriculum decisions. Still, the labor board overturned an earlier ruling barring grad students from engaging in collective bargaining.

That 2016 decision ushered in a wave of union activity at universities across the country. Teaching and research assistants at 16 private universities have since filed petitions or participated in elections to form unions, according to Hunter College’s National Center for the Study of Collective Bargaining in Higher Education and the Professions. Just last week, Harvard graduate students voted to join the UAW.