Illinois Gov. Pat Quinn today is expected to sign a bill that legalizes civil unions. About 1,000 people are expected to be on hand for the ceremony at the Chicago Cultural Center.

Illinois legislators approved civil unions late last year. The bill would allow same sex couples hospital visitation rights and the ability to share insurance policies. State Rep. Greg Harris was instrumental in getting the bill passed.

“This is a huge moment for people in Illinois and people feel that they have a lot of their future invested in this,” Harris said.

But David Smith, with the Illinois Family Institute, said he opposes the legislation. He said civil unions could lead to the state allowing gay marriage.

“Marriage always will be the union of one man and one woman,” Smith said.

Governor Pat Quinn calls the legislation a civil rights issue. Once signed, the measure will go into effect June 1st.