(CBS) — The former music director at a Catholic parish has filed a discrimination complaint with the Equal Employment Opportunity Commission, charging he was illegally fired for his intention to marry his same-sex partner.

CBS 2’s Derrick Blakley has more on a battle that pits civil rights against religious freedom.

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“It is with deep regret that I have to pursue this course of action,” plaintiff Colin Collette says.

For 17 years, Collette was music director at Holy Family Parish in Inverness. But last July, he was fired after announcing his intention to marry his longtime same-sex partner.

“It saddens me to have this integral part of my life taken away because I have chosen to enter into a marriage, as is my right under Illinois law,” he says.

Illinois law also bars discrimination due to sexual orientation.

But DePaul University law professor Jeffrey Shaman says that same law provides wide exemptions for religious institutions.

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“It’s not at all clear that he would have a winning claim against the church,” Shaman says.

Collette met with Francis Cardinal George, with another meeting promised but never scheduled. Collette and his attorneys were hoping for a fresh review from new Archbishop Blase Cupich.

Asked about the lawsuit today, the archbishop seemed content to leave the matter in the hands of the lawyers.

“We do intend to respond in the appropriate form in which it was filed, and I think that’s probably the best way for us to respond to it,” Cupich said.

Federal court rulings give churches wide latitude in choosing their ministers, even non-ordained ones. That means the discrimination claim may not be easy to win in court.

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Collette wants his job back, but the parish has already hired a replacement.