The U.S. Postal Service is under scrutiny over its activities during the 2016 political campaigns.

FOX's Rachel Sutherland reports from Washington:

A report from the Office of Special Counsel shows the U.S. Postal Service allowed unionized workers to go on leave without pay in 2016 to work for Hillary Clinton's presidential campaign and other Democratic candidates.

So many workers took leave, the Postal Service incurred substantial overtime costs. The Office of Special Counsel says the USPS engaged in systemic violations of the Hatch Act, which limits political activities of federal employees.

In Washington, Rachel Sutherland, FOX News.

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