Washington (CNN) The US Agriculture Department's inspector general has concluded the department may have violated the law when deciding to relocate two offices from the Washington, DC, area.

USDA has justified its decision to relocate the Economic Research Service and National Institute of Food and Agriculture offices to the Kansas City area for both financial reasons and to put the researchers closer to the agricultural heartland.

But it is seen by critics as a swipe at the agency's scientific expertise and was largely unwelcome with agency employees . Those offices unionized, and around 70% told union organizers they would not make the move. Some physically turned their backs on Agriculture Secretary Sonny Perdue at a public meeting where he addressed the move.

White House acting chief of staff Mick Mulvaney said Friday that the move is part of the administration's approach to "drain the swamp" in Washington.

"More than half the people quit. Now, it's nearly impossible to fire a federal worker," he said. "What a wonderful way to sort of streamline government and do what we haven't been able to do for a long time."

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