 
On November 8, 2016, Illinois voters approved the Illinois Transportation Taxes and Fees Lockbox Amendment, a legislatively referred constitutional amendment that prohibits lawmakers from using transportation funds for anything other than their stated purpose.
Amendment text.
The amendment added the following a Section 11 to Article IX of the Illinois Constitution:
 ;templatestyles src="Template:Blockquote/styles.css" / ;Section 11. Transportation Funds
(a) No moneys, including bond proceeds, derived from taxes, fees, excises, or license taxes relating to registration, title, or operation or use of vehicles, or related to the use of highways, roads, streets, bridges, mass transit, intercity passenger rail, ports, airports, or to fuels used for propelling vehicles, or derived from taxes, fees, excises, or license taxes relating to any other transportation infrastructure or transportation operation, shall be expended for purposes other than as provided in subsections (b) and (c).
(b) Transportation funds may be expended for the following: the costs of administering laws related to vehicles and transportation, including statutory refunds and adjustments provided in those laws; payment of highway obligations; costs for construction, reconstruction, maintenance, repair, and betterment of highways, roads, streets, bridges, mass transit, intercity passenger rail, ports, airports, or other forms of transportation; and other statutory highway purposes. Transportation funds may also be expended for the State or local share of highway funds to match federal aid highway funds, and expenses of grade separation of highways and railroad crossings, including protection of at-grade highways and railroad crossings, and, with respect to local governments, other transportation purposes as authorized by law.
(c) The costs of administering laws related to vehicles and transportation shall be limited to direct program expenses related to the following: the enforcement of traffic, railroad, and motor carrier laws; the safety of highways, roads, streets, bridges, mass transit, intercity passenger rail, ports, or airports; and the construction, reconstruction, improvement, repair, maintenance, operation, and administration of highways, under any related provisions of law or any purpose related or incident to, including grade separation of highways and railroad crossings. The limitations to the costs of administering laws related to vehicles and transportation under this subsection (c) shall also include direct program expenses related to workers' compensation claims for death or injury of employees of the State's transportation agency; the acquisition of land and the erection of buildings for highway purposes, including the acquisition of highway rights-of-way or for investigations to determine the reasonable anticipated future highway needs; and the making of surveys, plans, specifications, and estimates for the construction and maintenance of flight strips and highways. The expenses related to the construction and maintenance of flight strips and highways under this subsection (c) are for the purpose of providing access to military and naval reservations, defense-industries, defense-industry sites, and sources of raw materials, including the replacement of existing highways and highway connections shut off from general use at military and naval reservations, defense-industries, and defense-industry sites, or the purchase of rights-of-way.
(d) None of the revenues described in subsection (a) of this Section shall, by transfer, offset, or otherwise, be diverted to any purpose other than those described in subsections (b) and (c) of this Section.
(e) If the General Assembly appropriates funds for a mode of transportation not described in this Section, the General Assembly must provide for a dedicated source of funding.
(f) Federal funds may be spent for any purposes authorized by federal law.
Passage in the legislature.
The amendment had been sponsored in the legislature by Democrat Brandon Phelps.
Only four members of the Illinois House of Representatives voted against placing the amendment on the ballot (Democrats Barbara Flynn Currie, Laura Fine, Elaine Nekritz, and Pamela Reaves-Harris). The four published an op-ed in which they argued, "Experience has demonstrated that unexpected events can have drastic impacts on our state budget. A major natural disaster or economic turmoil can blow huge holes in a budget, even in states in healthy financial condition - which Illinois is decidedly not. This amendment would severely curtail the ability of the state to react to these types of events."
Election.
In order to be approved, the measure required either 60% support among those specifically voting on the amendment or 50% support among all ballots cast in the elections.
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The ballot summary read, ;templatestyles src="Template:Blockquote/styles.css" / ;
Endorsements.
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