5 GCA § 23105: Mileage Allowance.

Persons authorized to travel at government expense shall, in accordance with regulations and whenever such mode of transportation is authorized or approved as more advantageous to the government, be paid in lieu of transportation a maximum personal vehicle mileage allowance rate equal to the mileage reimbursement rate provided by the Federal government, contained in the Federal Travel Regulations, to its employees for the use of personal vehicles when engaged on official business.