(a) Each member of the Legislature is entitled to be reimbursed, upon submission of an expense voucher, for expenses incurred incident to travel in the performance of his or her duties as a member of the Legislature or any committee of the Legislature, whether the committee is operating under general law or resolution, including, but not limited to, attendance at party caucuses held in advance of the date of the assembly of the Legislature in regular session in odd-numbered years for the purpose of selecting candidates for officers of the two houses, at a rate equal to that paid by the travel management office of the Department of Administration for the most direct usually traveled route, if travel is by private automobile, or for actual transportation costs for direct route travel, if travel is by public carrier, or for any combination of those means of transportation actually used, plus the cost of necessary taxi or limousine service, tolls and parking fees in connection with the travel, but during any regular, extension of regular or extraordinary session, travel expenses shall not be paid to any member for more than one round trip to and from the seat of government and to and from his or her place of residence for each week of the session.

(b) In addition to the travel expense in subsection (a) of this section, the President of the Senate and the Speaker of the House of Delegates are entitled to be reimbursed as provided in subsection (a) of this section, upon submission of an expense voucher, for expenses incurred incident to travel which is related to their duties as presiding officers of the respective houses of the Legislature, but which takes place when the Legislature is not in regular, extension of regular or extraordinary session and interim committees are not meeting.

(c) The rate paid for mileage pursuant to this section may change from time to time in accordance with changes in the reimbursement rates established by the travel management office of the Department of Administration, or its successor agency.