SANTA FE (Reuters) - New Mexico's governor broke the law by firing all members of the state's Labor Relations Board and unions seek to reverse the move by an appeal to the state Supreme Court, a union leader said on Thursday.

New Mexico AFL-CIO president Christine Trujillo said she was "very, very concerned" with Governor Susana Martinez's efforts to dismantle organized labor in the state.

"She's trying to destroy all the efforts that we have made over the past ten years," Trujillo said. "We feel like she's been in the same workshop as every other Republican governor to undo collective bargaining."

Martinez, elected in November, on March 1 fired all three members of the New Mexico Public Employee Labor Relations Board, which holds hearings and renders decisions on labor complaints.

A spokesman for Martinez said the firings were within the scope of her authority.

"The law allows the governor to remove the members of the Public Employee Labor Relations Board, which was done as part of the ongoing review of boards, commissions and appointments," said the spokesman, Scott Darnell.

But a dozen union organizations filed a writ of mandamus on Wednesday asking the state Supreme Court to rule that Martinez overstepped her authority by the firings.

She had also forced out the labor board's executive director in early February, court documents said.

"She was not in her legal right," Trujillo said.

In the court filing, Shane Youtz, a lawyer for the unions, said that while the governor does have the right to dismiss certain board or commission members appointed by her Democratic predecessor, members of the labor board are excluded because that board enforces the Public Employees Bargaining Act.

"She has broad authority to dismiss but the Public Employee Bargaining Act is subject to control by the legislature," Youtz said. "The PEBA is drafted such that she has no discretionary power over this board."

Trujillo said there are several pending cases to be heard before the Labor Board but are now "in a state of limbo."

Among the pending cases is one against the administration of former Governor Bill Richardson regarding state employees being furloughed without pay for budget reasons.

(Editing by Corrie MacLaggan and Peter Bohan)

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