625 ILCS 5/3-606
Upon receipt of a request of a member of the General Assembly, accompanied by the appropriate application and fee, the Secretary of State shall issue to the member 2 plates as described in this Section. The special plates issued under this Section shall be affixed only to passenger vehicles of the first division, motorcycles, autocycles, and motor vehicles of the second division weighing not more than 8,000 pounds. Except as otherwise provided in this Section, if the member so requests, the Secretary shall issue 2 sets of such registration plates for use on 2 different motor vehicles. A member may request that the Secretary of State issue registration plates in the name of a corporation when the corporation owns or leases the vehicle to be registered and the member is an officer or director of that corporation. Such registration plates shall be issued for a 2-year period beginning January 1 of each odd-numbered year and ending December 31 of the subsequent even-numbered year. If the application is from a member of the Senate, there shall appear on the rear plate, in addition to the designation of the State and the year for which the license was issued, the word "official" and appropriate wording or abbreviation indicating that the holder is a member of the Senate, followed by the number of the senatorial district of the member. On the front plate, there shall appear appropriate wording or abbreviation indicating that the holder is a member of the Senate. If the application is from a member of the House of Representatives, there shall appear on the rear plate, in addition to the designation of the State and the year for which the license was issued, the word "official" and appropriate wording or abbreviation indicating that the holder is a member of the House of Representatives, followed by the number assigned to the member. On the front plate, there shall appear appropriate wording or abbreviation indicating that the holder is a member of the House of Representatives. Numbers 1 through 118 shall be assigned and members with the longest length of service as members of the legislature shall be given the lower numbers.
When members have an equal length of service, the lower numbers shall be given in alphabetical order based on surnames.
A member of the General Assembly who has a disability as defined under Section 1-159.1 may request one set of specialized plates which display the International Symbol of Access and shall be subject to the provisions within Section 3-616. The set of specialized plates displaying the International Symbol of Access shall only be issued along with the assignment of a corresponding disability placard that must be displayed in the vehicle. The surviving spouse of the member shall not be entitled to retain this plate.
625 ILCS 5/3-606