LITTLE ROCK — The American Civil Liberties Union of Arkansas can intervene in a lawsuit over a Fayetteville city ordinance that sought to ban discrimination against lesbian, gay, bisexual and transgender people, a judge ruled Tuesday.

Washington County Circuit Judge Doug Martin said in a two-page order, without comment, that the ACLU can intervene in the suit against the city of Fayetteville originally brought by the group Project Fayetteville, which later was joined by the state of Arkansas.

In 2014, the Fayetteville City Council approved an ordinance prohibiting discrimination based on sexual orientation or gender identity, but voters repealed it later that year. In September 2015, Fayetteville voters reversed themselves and voted to approve a similar ordinance.

Between the repeal of the first ordinance and the passage of the second, the state Legislature approved Act 137 of 2015,which prohibits cities and counties from passing ordinances that prohibit discrimination on any basis not in state law. Arkansas’ civil rights law does not include protections for LGBT people.

Project Fayetteville, a group formed to oppose the ordinance, sued to have it struck down, but Washington County Circuit Judge Doug Martin ruled in March that the ordinance did not violate Act 137. The state joined Project Fayetteville and other opponents of the ordinance in appealing that ruling.

In February, the state Supreme Court ruled that the ordinance is barred by Act 137. The high court sent the case back to circuit court without ruling on whether the state law is constitutional, an issue the parties are now fighting over in circuit court.

The ACLU moved to intervene on behalf of the group PFLAG Fayetteville/Northwest Arkansas and three LGBT residents of Fayetteville, arguing that the Legislature’s attempt to nullify Fayetteville’s local non-discrimination ordinance violates their constitutional right to equal protection and would leave them vulnerable to discrimination in housing, employment, and public accommodations.