The Texas Supreme Court ruled Friday that Houston has to either repeal its equal rights ordinance or let the public vote on it. Getty Images

The fourth-largest city in the United States may soon be forced to shelve a provision intended to protect its lesbian, gay, bisexual and transgender residents. The Texas Supreme Court ruled Friday that Houston must either repeal the Houston Equal Rights Ordinance or let the public vote on it in November, Slate reported.

The ordinance, also referred to as HERO, passed the city council in spring 2014. Soon after, opponents gathered signatures on a petition asking the city to either rescind the ordinance or let people vote on it. The city secretary initially accepted the document, but the mayor and city attorney later discovered that some of the signatures had been forged -- and therefore were invalid. A judge agreed with them, so the opposition appealed.

But the state Supreme Court's Friday decision reversed that ruling, saying that Houston must take action because the city secretary originally verified the document. "We agree ... that the City Secretary certified their petition and thereby invoked the City Council's ministerial duty to reconsider and repeal the ordinance or submit it to popular vote," the opinion read. "The legislative power reserved to the people of Houston is not being honored."

The ordinance prevents discrimination based on sexual orientation and gender identity -- as well as sex, race, color, ethnicity, national origin, age, religion, disability, pregnancy, genetic information, military status, family or marital status, the Houston Chronicle reported. City employment, services, contractors, housing, public accomodations and private employment are affected.

Houston's city council now must repeal the ordinance by Aug. 24 or put the referendum on the November ballot. Both sides seem to think they'll win.

"No matter the color of your skin, your age, gender, physical limitations, or sexual orientation, every Houstonian deserves the right to be treated equally," Mayor Annise Parker, who is openly gay, told the Chronicle. "To do otherwise hurts Houston's well-known image as a city that is tolerant, accepting, inclusive and embracing of its diversity. Our citizens fully support and understand this and I have never been afraid to take it to the voters."

Republican Gov. Greg Abbott released a statement saying he supported the Supreme Court decision because it returned jurisdiction to voters and showed them their values were out of the government's reach. “Freedom of expression can only exist once government removes itself from stifling free speech, repressing religious liberty and interfering with the lives of its citizens," Abbott said.