One hundred and forty-seven years after its adoption, the one-subject rule of the Ohio Constitution continues to generate debate. What emerges from its origin at the 1850-1851 Ohio Constitutional Convention, its early application in the Pim decision and its survival at the 1873-1874 Ohio Constitutional Convention, however, are the principles that the purpose of the rule is (1) to notify legislators of the content of bills on which they vote after having dispensed with the required reading; and (2) to avoid the joinder of unrelated measures that could not win separate support during the legislative process. The one-subject clause thus gives the presiding officer of each house of the General Assembly a basis for ruling out of order measures that he or she deems to fall outside of the inherent scope of pending legislation. Enforcement of the one-subject rule historically has been a legislative prerogative. This approach recognizes the latitude necessary for comprehensive legislation on complex subjects. It likewise constrains most definitional second-guessing by the executive and judicial branches. Only in the most "manifestly gross and fraudulent" circumstances have courts allowed private litigants to apply the provisions of the one-subject rule to enacted legislation.
John J. Kulewicz,
The History of the One-Subject Rule of the Ohio Constitution,
45 Clev. St. L. Rev.
available at https://engagedscholarship.csuohio.edu/clevstlrev/vol45/iss4/6