A U.S. judge clarified on Tuesday that an order restricting billionaire Elon Musk's government cost-cutting effort from accessing the Treasury Department's payment systems does not apply to Treasury Secretary Scott Bessent.

The order came in response to a lawsuit filed by 19 attorneys general accusing the president of failing to faithfully execute the nation’s laws when he let DOGE comb through federal computer systems.

This primer explains what the Bureau of the Fiscal Service does, how it has traditionally been managed by career civil servants, and the risks posed by tampering with the system.