5 U.S. Code § 5705
5.U.S. Code § 5705 is about Advancements and deductions. It is under Subchapter I (Travel And Subsistence Expenses; Mileage Allowances) of Chapter 57 (Travel, Transportation, And Subsistence) of Subpart D (Pay and Allowances) of Part III (Employees) of Title 5 (Government Organizations and Employees) of the Code.
An agency may advance, through the proper disbursing official, to an employee entitled to per diem or mileage allowances under this subchapter, a sum considered advisable with regard to the character and probable duration of the travel to be performed. A sum advanced and not used for allowable travel expenses is recoverable from the employee or his estate by—
(1)setoff against accrued pay, retirement credit, or other amount due the employee;(2)deduction from an amount due from the United States; and(3)such other method as is provided by law.
