WASHINGTON (AP) — An arbitrator has ruled that former Schools Chancellor Michelle Rhee improperly fired 75 new District of Columbia teachers in 2008 and is ordering them reinstated with two years of back pay.

Arbitrator Charles Feigenbaum found that the school system never told the teachers why they were being fired and gave them no chance to explain or refute what their principals reported to school system officials.

In the decision released Tuesday, he wrote that the process was "arbitrary and capricious."

“The main issue here was that teachers were terminated without even being informed of their transgression,” said Mindy Holmes the lead attorney on this case, in a statement. “We fought to protect the process that DCPS must use when it seeks to terminate teachers.”

Washington Teachers' Union President Nathan Saunders says mass firings without explanation are irresponsible and costly.

“The unfounded and unfair way of firing teachers under the Fenty/Rhee administration must change under the Gray administration to deliver high quality education and leverage limited financial resources,” Saunders said in a statement.

“The WTU will legally pursue cases of our members who have been improperly terminated.”

D.C. Public Schools spokesman Fred Lewis says officials are reviewing options to appeal or challenge the decision but have not decided how to proceed.

AFRO staff contributed to this story.