By ANNA M. PHILLIPS

The usually friendly relationship between the state teachers union and the State Department of Education fissured on Tuesday with the union’s announcement that it was taking the state to court over new teacher evaluation rules.

The lawsuit, which was filed in the State Supreme Court in Albany on Monday, accuses the Board of Regents — the state’s policy making body on education — of giving districts more power to use test scores in teacher evaluations than the law allows.

The law in question was passed last year, with the union’s support, as part of New York’s successful effort to win a $700 million federal Race to the Top grant.
Using a 100-point scale, the law dictated that 20 points of a teacher’s evaluation come from students’ progress on the state exams and that another 20 points come from local assessments that would be negotiated with the unions. The remaining 60 percent would come from subjective measures like principals’ evaluations.

In May, responding to criticism from Gov. Andrew M. Cuomo, the Board of Regents voted to give school districts the option of weighing the state tests more heavily so they would count for 40 points. Proponents of this plan said that asking financially struggling districts to create their own local tests was unrealistic.

But Richard C. Iannuzzi, president of the New York State United Teachers union, said that the state’s guidelines were more about evaluating teachers “quickly and cheaply, instead of doing it right.”

He said the guidelines would encourage poorer districts to save money by using the state tests, effectively diminishing the quality of their teacher evaluations.

“For a school district to opt to count a state test twice, the cost to it is close to zero,” he said. “But for a school district to provide professional development, it’s going to cost more. The wealthy school districts can provide that, but the poorer school districts will find that they have no choice.”

Merryl Tisch, chancellor of the Board of Regents, said that the state teachers union had made no secret of its plans to sue once the regulations were passed. The union’s suit has little basis, she said, because districts still have to reach a deal with their unions on whether to create local assessments or use the state exams.

“I am hoping the court will make a quick decision to allow the implementation of the teacher evaluation system to move forward,” she said.

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