[Interest on Late Payments of Mandatory Employee Incentive Awards]

The Internal Revenue Service (IRS) and the National Treasury Employees Union (NTEU) requested a decision regarding the legality of a proposed collective bargaining provision that would require IRS to pay interest if it made a late payment of a mandatory award to an employee. GAO held that the interest provision was consistent with the Back Pay Act, which applied when an agency failed to comply with award payment deadlines it agreed to in collective bargaining. Accordingly, the provision was legally supportable.