The Supreme Court says a former top lawyer at the National Labor Relations Board served in violation of a federal law governing temporary appointments.

The 6-2 ruling on Tuesday limits the president's power to fill vacant government posts while nominations are tied up in partisan political fights.

The justices said that Lafe Solomon was not allowed to serve as acting general counsel of the agency that enforces labor laws while he was at the same time nominated to fill that role permanently.

President Barack Obama named Solomon acting general counsel in June 2010 and he held the office until Nov. 4, 2013. But he never won Senate confirmation because Republicans viewed him as too favorable to labor unions.