ROCKVILLE, Md. (AP) – Montgomery County voters will decide whether to keep an anti-discrimination law with broad protections for transgender people.

Circuit Court Judge Robert Greenberg ruled July 31 that advocates for gay and transgender rights missed a critical deadline for challenging the county Board of Elections, which certified a petition to put the law to a vote on the November ballot.

Greenberg agreed with advocates’ argument that elections officials miscalculated the number of signatures required for a referendum on the measure. But he said the challenge was filed “too late.”

Last year, a measure banning discrimination against transgender individuals in housing, employment and public accommodations was signed into law, but opponents blocked it with a petition to force a referendum.

Jonathan Shurberg, an attorney for Equality Maryland, the gay and transgender rights group, said he intends to appeal the decision “vigorously and promptly.”

“We were right,” he said. “The question is one of timeliness, and we don’t believe the judge rightly applied the law.”

County officials followed state election board guidelines in setting the mark for certification at 25,000 signatures, or 5 percent of registered voters, said Kevin Karpinski, an attorney for the Board of Elections. That number did not include 52,000 registered voters listed as “inactive” because they have not participated regularly in elections.

Greenberg agreed with Shurberg’s argument that the county should have included inactive voters, increasing the number of signatures needed to reach the 5 percent mark. But he said the challenge should have been filed by Feb. 20, the day the board verified the first batch of signatures. The request for judicial review was filed March 14.

“In a pre-election context, time is of the essence,” Greenberg wrote.

Opponents, led by the group Citizens for Responsible Government, collected signatures to force a referendum on the law, blocking it from taking effect.

Equality Maryland challenged the validity of the signatures, but Greenberg rejected Shurberg’s argument that election law requires an individual to sign a petition exactly as his or her name appears on the voter registration rolls. That requirement, Greenberg said, “would lead to absurd results, and potentially culminate in the disenfranchisement of otherwise eligible voters.”

The law was the result of a democratic legislative process that included public discussions, said Councilmember Duchy Trachtenberg, who introduced the measure.

“Even if this does go on the ballot,” she said, “I firmly believe that the voters of Montgomery County will reject discrimination.”