Las Vegas (AP) – A Las Vegas judge has granted a 15-day restraining order to prevent southern Nevada police and prosecutors from enforcing a voter-approved statewide smoking ban that was to take effect Friday.

Clark County District Court Judge Douglas Herndon said Thursday that there was a sufficient likelihood that a group of southern Nevada business owners could persuade him the ban was unconstitutional, and ordered both sides to present their cases at a Dec. 19 hearing.

Herndon was cautious to note that he was not taking a position on the ban or undermining the vote of the people.

„In terms of the view of activist judges, this is not an issue of my telling the voters their vote is wrong. It’s an issue of the constitutionality of the law they voted on,“ Herndon said.

The groups‘ lawyer, Kirk Lenhard, had asked for a „breathing period“ in which both parties could prepare briefs on the constitutionality of the measure.

The Clean Indoor Air Act, approved as Question 5 on the Nov. 7 ballot, 54 percent to 46 percent, would ban smoking in bars that serve meals; in slot machine sections of grocery and convenience stores; and at video arcades, shopping malls, schools and day-care centers.

It would allow smoking in the gambling areas of casinos.

The business group filed suit Tuesday asking for an injunction and a restraining order to keep law enforcement officials from enforcing the law, claiming it was unconstitutional, too vague to comply with, and unfairly discriminated against some businesses.

Besides the attorney general’s office, the group named only Las Vegas-area agencies as defendants in the suit, so the restraining order applies only to those agencies, Herndon said. His ruling does not affect enforcement of the smoking ban in other parts of the state, and the attorney general’s office said its role was to defend the state law, not enforce its provisions.

It wasn’t immediately clear how evenly the ban would be enforced outside of southern Nevada.

Sparks Police Cmdr. Steve Asher said the department will prioritize calls related to the ban.

„We wouldn’t out-and-out, completely ignore that. If someone was to call and say, ‚this is what’s going on,‘ we’d take a case and submit it to the city attorney,“ he said.

Elko County Sheriff Neil Harris said he needs more information before he starts enforcing the law in his rural eastern Nevada county.

If a smoker lights up in a restaurant Friday, „we’re not going to do anything with it, we need more direction from the attorney general or the district attorney before we can enforce it,“ Harris said.

Lenhard pointed to guidelines recently drafted by the Southern Nevada Public Health District as evidence the district was „filling in the blanks“ left by holes in the measure.

„What has happened here is the health department is now legislating,“ he said.

Southern Nevada Public Health District lawyer Stephen Minagil said because the measure „is open to interpretation … does not make the statute constitutionally vague.“

Business owners, which include bars and operators of convenience and grocery store slot machines, argued that there would be no harm in withholding enforcement of the law until a court could rule on their claims.

„We’ve been smoking in bars for 140 or 145 years. How is two weeks additional time smoking in bars going to be the end of the universe?“ Lenhard argued. „It is not.“

Minagil, along with the Nevada attorney general’s office, argued the business owners had not proved they would be „irreparably harmed“ if the measure were to be enacted immediately.

„What harm is it to remove the ash tray, post the sign and ask people to simply go outside?“ Minagil said.

He called the business owners‘ claims of possible employee layoffs and lost business „speculative.“

But Herndon said the law requires a lower threshold for obtaining a restraining order in a constitutional question.

Business owners were joined in the case Thursday by the Nevada Association of Tavern Owners, bringing the number of plaintiffs seeking to challenge the ban to more than 220 establishments.

The association’s lawyer Mark, Ferrario, said his group will add an argument to the case. Ferrario called the smoking ban a „taking of airspace“ in which the state was inappropriately usurping and controlling space belonging to the business.

„We believe that if you’re going to take that there needs to be compensation,“ he said.