Ohio State Issue 1 (2004)

Section 15.11 is a provision in the Ohio Constitution that makes it unconstitutional for the state to recognize or perform same-sex marriages or civil unions. Approved as a constitutional amendment in 2004 under the name of "Issue One", it received support from 61.7% of voters.

The text of the amendment states:

Only a union between one man and one woman may be a marriage valid in or recognized by this state and its political subdivisions. This state and its political subdivisions shall not create or recognize a legal status for relationships of unmarried individuals that intends to approximate the design, qualities, significance or effect of marriage.

The LGBT rights organization Equality Ohio was founded in response to the passage of Issue 1.

...
Wikipedia