LOS ANGELES (CBSLA.com) — Teachers unions suffered a major legal setback Tuesday after a Los Angeles Superior Court judge ruled that state laws governing teacher tenure are unconstitutional.

As part of the ruling (PDF) in the landmark education equality lawsuit Vergara v. California, Judge Rolf M. Treu issued an injunction blocking tenure laws but also placed a stay on the ruling pending an appeal.

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The lawsuit was filed in May 2012 by nine families represented by the group Students Matter, which sought to overturn regulations that allow teachers to earn tenure after 18 months and the rules that govern which teachers are laid off.

High-profile officials including former mayor Antonio Villaraigosa and LAUSD Superintendent John Deasy were among those to speak out against teacher seniority rules.

In a statement, Deasy said: “This is a truly historic day for our education system. Today’s decision is a call to action to begin implementing, without delay, the solutions that help address the problems highlighted by the Vergara trial. Every day that these laws remain in effect is an opportunity denied. It’s unacceptable, and a violation of our education system’s sacred pact with the public.”

Plaintiff’s attorney Theodore Boutrous also hailed the decision.

“This is a monumental day for California’s public education system,” said Boutrous. “By striking down these irrational laws, the court has recognized that all students deserve a quality education. Today’s ruling is a victory not only for our nine plaintiffs; it is a victory for students, parents, and teachers across California.”

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KNX 1070’s Pete Demetriou reports union members and their supporters voiced disappointment with the ruling.

“We believe the judge fell victim to the anti-union, anti-teacher rhetoric of one of America’s finest corporate law firms,” said Joshua Peshtal, President of the California Federation of Teachers.

During the trial, Boutrous argued that five laws should be deemed unconstitutional, saying tenure laws made it too time-consuming and expensive to dismiss ineffective educators.

“Teaching is the one profession in the world where you cannot tell a person they are not doing a good job,” he said during his closing argument.

In response, lawyer James Finberg, who represented the teacher unions, argued that the laws help prevent teachers from being hired and retained for reasons involving favoritism and politics. Finberg also claimed that within three months an administrator can make a “well-informed decision” as to whether a probationary teacher should be retained.

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