The American Civil Liberties Union and the ACLU of Mississippi filed a lawsuit Monday on behalf of a gay couple challenging a Mississippi bill that lets certain businesses refuse to serve gay couples based on religious objections.

This lawsuit in the U.S. District Court for the Southern District of Mississippi calls the bill “unconstitutional on its face,” saying that it effectively makes any same-sex union a “second-tier marriage,” and asks for an injunction to stop the measure from becoming effective in July.

According to the suit, Nykolas Allen and Stephen Thomas are engaged and plan to get married within the next three years. However, they argue that the law would give same-sex couples looking to get married “a unique set of burdens that are not inflicted on marriages of different-sex couples.”

The lawsuit in Mississippi was announced on the same day that North Carolina sued the Justice Department amid a fight there over a bill that bars transgender people from using bathrooms that don’t match the gender listed on their birth certificates. Mississippi’s bill was also signed by its governor on the same day that PayPal said it would abandon plans to open a facility in Charlotte due to North Carolina’s law.

Mississippi’s law was signed by Gov. Phil Bryant (R) in April and goes into effect on July 1. This measure says it is meant to protect “sincerely held religious beliefs or moral conviction,” including the belief that marriage is limited to unions between a man and a woman and that gender is “determined by anatomy and genetics at time of birth.”

The Protecting Freedom of Conscience from Government Discrimination Act protects businesses or individuals who refuse to provide goods, services or facilities for a gay wedding because of religious or moral objections.

The law also says that government employees who authorize or issue marriage licenses or perform marriages can recuse themselves because of their beliefs, so long as these licenses and marriages are “not impeded or delayed as a result of any recusal.” When he signed it, Bryant said that the bill would “not limit any constitutionally protected rights or actions” and was meant to exist in “the most targeted manner possible.”

Josh Block, a staff attorney for the ACLU, said in a statement that the group hoped the lawsuit would “stop as much of [the bill] as possible” before it went into effect.

“At a time when we’re supposed to be excited as a couple engaged to be married, this law permits discrimination against us simply because of who we are,” Allen and Thomas, members of the ACLU of Mississippi, said in a statement released by the ACLU. “This is not the Mississippi we’re proud to call home. We’re hopeful others will come to realize this and not allow this harmful measure to become law.”

Groups had called on Bryant to veto the bill, calling it discriminatory and worrying about the impact they had seen in other states considering or adopting controversial bills. Socially conservative groups had praised Mississippi’s measure and hailed Bryant for resisting the pushback from rights organizations and businesses.

Bryant’s office did not immediately respond to a request for comment Monday.