The high court's decision means that in the eyes of the law, same sex couples who are legally married cannot be denied their equal right to federal benefits. But in Illinois, gay couples cannot legally marry.
A bill to change that passed the state Senate in February, but was never called for a vote in the House.
"Boy, it is bittersweet for us in Illinois."
Bernard Cherkasov heads Equality Illinois, the state's oldest gay-rights organization.
"And every day that goes by is another day where Illinois is a state of two classes of citizens. Those citizens who are able to get recognition, and those who can't. And it's up to Illinois lawmakers to remedy that on the first opportunity that they have."
Same sex couples can enter civil unions in Illinois, but that doesn't give them access to the same 1,100 federal benefits of marriage.