Washington (CNN) -- The Supreme Court sided with Congress on Thursday in the high-stakes power struggle over presidential recess appointments, in which officials are placed in top government jobs temporarily without Senate approval.
The unanimous ruling by the court against the Obama administration could invalidate hundreds of decisions by the National Labor Relations Board, the federal agency at the center of this legal fight.
At issue is whether three people named by President Barack Obama to the board were ineligible to serve because their appointments were made while the Senate was technically in a "pro forma" session during the 2011-12 winter holiday break.
The Constitution allows a president to fill temporary appointments during a recess, without congressional approval. But more recently, lawmakers have sought to thwart certain appointments by never technically shutting down the Senate.
The closely watched constitutional and political confrontation over the practice has accelerated because of partisan gridlock in Congress.
The court's opinion will not have an immediate effect, since Democrats controlling the Senate imposed rules making it harder for Republicans to block Obama's nominees. But a change in Senate control after November's midterm elections could renew the disagreements.
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