Entitlement to Reimbursement for Travel Expenses

An advance decision was requested concerning the legality of paying certain travel expenses which an employee incurred during a temporary duty assignment. At the outset of the temporary detail, it could not be determined how long the employee would be assigned to work at the temporary location. The agency failed to provide the employee with travel orders establishing any method for reimbursing expenses. Nevertheless, the employee submitted several vouchers claiming per diem for travel expenses, and these vouchers were paid. After the termination of his detail, the employee contacted the agency and questioned the amount of his reimbursement contending that he had lost money because the amount he had claimed did not offset the costs of traveling for return visits. The agency asked GAO whether the employee was entitled to per diem at the rate paid or at a higher rate and whether he was entitled to return travel in lieu of per diem. Written authorization should have been issued prior to the incurrence of travel expenses. None of the prior authorization steps were undertaken in this case. As a result of the agency's oversignt, the employee's right to a specific per diem rate did not vest at the time of travel because no travel order was issued in connection with his temporary duty assignment. Thus, the general rule which disallows a retroactive modification of travel orders does not apply in this case. Therefore, GAO had no objection to the agency retroactively establishing a per diem entitlement for the employee. Since the employee owned a residence at the temporary duty site, the only lodging expenses incurred by the traveler which may properly be reimbursed are those which were incurred by reason of travel which were in addition to the usual expenses of maintaining his residence. The agency should establish a retroactive per diem entitlement incident to a duly executed travel authorization that reimburses the employee for the additional per diem expenses that he reasonably incurred. The employee's travel expenses are reimbursable to the same extent, including his voluntary trips to his original duty station. Accordingly, the employee's reclaim voucher could be paid consistent with the decision.