PHOENIX — In a case with nationwide implications, the U.S. Supreme Court ruled Thursday the town of Gilbert illegally blocked a tiny church from erecting temporary signs directing parishioners to services.

In a unanimous opinion, the court concluded the town acted improperly in permitting some signs to remain up for longer period than others. Justice Clarence Thomas, writing for the court, said that was an impermissible content-based regulation.

“The First Amendment ... prohibits enactment of laws ‘abridging the freedom of speech,’” Thomas wrote. “Under that clause, a government, including a municipal government vested with state authority has no power to restrict expression because of its message, its ideas, its subject matter, or its content.”

The breadth of that language suggests the impact will go well beyond religious organizations getting latitude in erecting signs.

Justice Elena Kagan, in a separate concurring opinion, agreed the Gilbert restrictions are unconstitutional, subjecting the church to restrictions that do not apply to similar kinds of signs. But Kagan, joined by two of her colleagues, warned the wording of the majority decision, authored by Thomas, could place other types of sign ordinances in legal jeopardy.

“Our communities will find themselves in an unenviable bind: They will have to either repeal the exemptions that allow for helpful signs on streets and sidewalks, or else lift their sign restrictions altogether and resign themselves to the resulting clutter,” Kagan wrote.

That conclusion did not escape local attention.

“Every city and town across the country, and not just in Arizona, is going to have to dig into its sign regulations to evaluate what changes will need to be made,” said Tucson City Attorney Mike Rankin.

He said one obvious conflict arises because political signs are given more favorable treatment than other kinds of messages. And the problem is statewide, Rankin noted, as Arizona law bars cities from prohibiting election signs for 60 days before the primary through 15 days after the general election and allows signs up to 16 square feet in residential areas and twice that big in commercial zones.

“That statute treats one type of message differently than others,” he said. “I would think the state would need to look at that.”

David Cortman of Alliance Defending Freedom, who argued the case for the church, agreed Thursday’s ruling means if Arizona lawmakers want to allow their own 32-square-foot campaign signs to remain up for months at a time, others must get the same right. He said in enacting that law, legislators concluded such signs are neither a hazard to traffic nor a cause of blight.

“What sense does it make to have an unlimited number of political signs out there ... but limit other types of speech?” Cortman said.

Ken Strobeck, executive director of the League of Arizona Cities and Towns, said the fallout could be even more drastic.

“The general conclusion is that there cannot be any kind of distinction in the regulation of signs based on anything having to do with their content,” he said. “So it doesn’t matter if it’s a mattress store or if it’s a flea market or if it’s a political candidate.”

Cortman, however, said he doubts Thursday’s ruling puts commercial speech on par with noncommercial speech. He said, though, it does mean communities cannot have different rules for different kinds of commercial speech.

The fight stems from the fact that the church, like many small congregations, has no building of its own.

Over the years, the group has instead conducted services in a variety of rented spaces, including public schools. It currently meets in a senior living center.

The church puts up signs directing would-be worshippers to the site.

But Gilbert regulations say the signs cannot be put out earlier than 12 hours before the service and must be removed one hour after it ends. And the rules limit the signs to no more than 6 square feet.

Political signs can be 32 square feet and remain in place for months. And even what the town calls “ideological signs” can be permanent and up to 20 square feet.

Attorneys for the town argued there are legitimate reasons for time limits on the signs, ranging from public safety to blight. But Thomas called that legally irrelevant.

“Innocent motives do not eliminate the danger of censorship presented by a facially content-based statute, as future government officials may one day wield such statutes to suppress disfavored speech,” he said. “That is why the First Amendment expressly targets the operation of the laws — abridgement of speech — rather than merely the motives of those who enacted them.”

The court rejected the town’s contention it was not illegally discriminating based on the content of the message.

“The town’s sign code ... singles out specific subject matter for differential treatment, even if it does not target viewpoints within that subject matter,” Thomas said.

“Ideological messages are given more favorable treatment than messages concerning a political candidate, which are themselves given more favorable treatment than messages announcing an assembly of like-minded individuals,” he continued. “That is a paradigmatic example of content-based discrimination.”

Thomas said the town’s argument has another flaw.

“The town has offered no reason to believe that directional signs pose a greater threat to safety than do ideological or political signs,” he wrote. “If anything, a sharply worded ideological sign seems more likely to distract a driver than a sign directing the public to a nearby church meeting.”

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