One day after 138 students, faculty and union workers were arrested by the New Haven Police, graduate teachers yesterday filed a charge against Yale University with the National Labor Relations Board.

The charge, brought by the Graduate Employees and Students Organization (GESO), says that Yale is retaliating against teaching assistants by "threatening to blackball them from future academic careers...," according to a press release by GESO.

Yale teaching fellows have been striking for five weeks in hopes that the University will recognize GESO's status as a collective bargaining unit. Eighty-seven graduate teaching fellows did not turn in grades for fall semester courses.

On Wednesday, approximately 300 people gathered outside the Hall of Graduate Studies to protest disciplinary action being taken against three teaching assistants accused of withholding grades.

Graduate student Diana Paton faced a disciplinary hearing Wednesday inside the graduate hall. Teaching assistant Cynthia Young was to face a hearing yesterday, and Buju Dasgupta was to face charges Monday.

Tom Conroy, a spokesperson for Yale, said the university had no formal response to the charges filed yesterday.

He said the university has responded to the graduate students' strike by pursuing disciplinary action and by refusing spring teaching positions to those now withholding grades.

"[Refusing teaching positions] was purely an administrative action that wouldn't affect their status as students," Conroy said. "The university has also made it clear that they may also be subject to the disciplinary procedure of the graduate school at Yale."

According to Jonas Zdanys, associate dean of the graduate school, such disciplinary procedure may include suspension or expulsion.

The university had extended the Jan. 2 deadline to turn in grades to Tuesday. According to school officials, 26 of 135 part-time instructors--graduate students who teach classes--still had not turned in grades by that time.

It is unclear how many of the school's 304 teaching fellows--graduate students who assist professors in lecture classes--missed the Tuesday deadline. According to GESO, the "grade strike" involves a total of about 200 people.

Yale spokesperson Gary Fryer said the deadline would be "softened" because of the delays in mail delivery caused by the snow.

The spring semester at Yale is scheduled to begin Monday.

This article was written using wire dispatches from the Associated Press.