SPRINGFIELD â What role does the treasurer play in state government? It depends on the state, but in Illinois, the treasurerâs role differs greatly from the state comptroller, who handles the check-writing as the stateâs chief fiscal officer. The treasurer, on the other hand, serves as the chief investment and banking officer in Illinois. According to the Illinois Constitution, âThe Treasurer, in accordance with law, shall be responsible for the safekeeping and investment of monies and securities deposited with him, and for their disbursement upon order of the Comptroller.â The current treasurer is Michael Frerichs, who first was elected in 2014 as a Champaign Democrat, defeating Republican Tom Cross by less than 0.5 percent of the vote. He gained reelection in 2018 by nearly 20 percent of the vote.