Teachers who worked outside of their regular school day to enter information in the Department of Education’s special education data system last year will get paid for their time, according to a labor decision announced today.

After teachers told the United Federation of Teachers that using the new system to record information about their everyday activities was burdensome, the union filed an official complaint in mid-2011. An arbitrator heard the union’s case and the Department of Education’s defense on 19 dates between December 2011 and October 2012 before concluding that the department’s implementation violated the union’s contract.

“After the longest arbitration in UFT history, the independent arbitrator, Jay Siegel, today concluded that the workday provisions in our contract had been violated,” UFT President Michael Mulgrew wrote in a letter to other union officials late today.

The city was permitted to introduce the system, called the Special Education Student Information System, without the union’s consent, Siegel decided. But he ruled that it was wrong to require educators to record their encounters with students when doing so required them to work outside of their contractual school day.

Now, the department must examine the system’s usage data and issue compensatory payments to anyone who used the system in the evenings or weekends between September 2011 and last month. The payments, which union officials say could go to more than 10,000 teachers and paraprofessionals, must be made by early March, according to the decision.

Department officials said the contract ruling comes in spite of SESIS’s usefulness for the city’s schools.

“We are disappointed with the decision,” said a spokeswoman, Connie Pankratz. She added, “However, this system has allowed the DOE to capture important information regarding special education services and, as noted by the arbitrator, there have been improvements to the system.”

And the arbitrator said he hoped the union would not need to seek repayment in the future for time teachers spend on SEIS. “Going forward, the parties would be best served by spending their time jointly analyzing and negotiating over what else needs to be done to improve the efficiency for SESIS users,” he wrote.

The arbitrator’s full decision is below: