ALBANY, N.Y. (AP) – The owners of an upstate New York wedding venue who were fined $13,000 after refusing to host a lesbian wedding are appealing the ruling.

The owners of Liberty Ridge Farm north of Albany refused to host the 2013 wedding of Melisa and Jennie McCarthy, citing their Christian beliefs that marriage is between a man and a woman. The state’s Division of Human Rights ruled that business owned by Robert and Cynthia Gifford violated New York’s anti-discrimination law.

Lawyers for the Giffords will argue before a mid-level appeals court Monday in Albany. The couple’s lawyers contend they were exercising their constitutional rights.

The New York Civil Liberties Union represented the McCarthys in their civil rights complaint. The NYCLU says the Giffords didn’t have the right to discriminate against the couple.