WASHINGTON (Legal Newsline) - Attorneys for the National Right to Work Foundation filed motions Monday with the National Labor Relations Board seeking to disqualify President Barack Obama's recent appointees.

The NRWF wants to keep the appointees from participating in the six cases that they have pending before the NLRB. The attorneys argue that the appointments are unconstitutional and, therefore, there is a lack of quorum which is necessary to hear the NRWF cases.

This legal challenge is the latest in an ongoing controversy over the constitutionality of President Obama's recent move to install three members to the NLRB as "recess appointees" despite the fact that some Republican senators say the U.S. Senate was not in recess.

NRWF attorneys have challenged the constitutionality of the appointments in federal court. An earlier motion is pending in the U.S. District Court for the District of Columbia.

If the Obama appointees are unconstitutional, then the NLRB has only two members and lacks a quorum to enact rules or enforce federal labor law under a U.S. Supreme Court precedent issued in 2010.

"Barack Obama's so-called recess appointments to the Labor Board clearly violate the U.S. Constitution," said Mark Mix, President of the National Right to Work Foundation.

"Because the Board does not have a legitimate quorum, it must cease hearing Foundation cases until a legitimate quorum is established."