SUMMERVILLE - Despite the blue lights and the green stripe with the yellow blaze "Police," the first thing that might catch the eye about this squad car is the yellow license plate on the front.

It reads, "Don't tread on me."

The car is one of a few among more than 60 marked Summerville squad cars that carry personalized plates - such as an American flag, "The Thin Blue Line" or another law enforcement motto, according to police Capt. Jon Rogers.

The issue with this one: The motto is used by the tea party, among other political groups.

Under state ethics law, the "use of government personnel or facilities for campaign purposes" is a misdemeanor punishable by as much as a $5,000 fine and a year in jail, according to the National Conference of State Legislators.

Even in the less-government-regulation environment of the Lowcountry, this plate could be seen as a mixed message coming from law enforcement.

But the motto, along with the image of a coiled Eastern diamondback rattler, is as authentically South Carolinian as Col. Christopher Gadsden and the flag carrying it that he proffered in 1775 to the newly organized American Navy.

So whether it's being used for "campaign purposes" is one of those eye-of-the-beholder things. A resident contacted The Post and Courier about concerns with it.

The department's policy is to allow officers to put personal touches on their cars - with approval - unless the sentiments are found to be offensive, Rogers said. This one hasn't been.

"It's on the Gadsden flag," Rogers said of the "Don't tread on me" motto. "It's not associated with any political party and it has a lot of history."

Mayor Bill Collins agreed. "I don't see a problem with it."

Others do, or at least want to head off this sort of issue. The potential political association is a live wire.

The saying "is definitely a reflection of the political culture we have in South Carolina," said Gibbs Knotts, a College of Charleston political scientist. "For public employees, there's pretty specific rules about doing political things with (public) resources or on the clock while you're at your job," he said.

The S.C. Public Safety Department and its agencies, such as Highway Patrol and transport police, do not allow alteration of vehicles unless approved by the patrol commander, said Lt. Kelley Hughes. The idea is to keep them uniformly recognizable, he said.

Some Lowcountry law enforcement agencies follow a version of that policy; others simply ban alteration. Dorchester County sheriff's deputies are not allowed to personalize the outside of vehicles because Sheriff L.C. Knight likes to have uniformity with the vehicles, said Chief Deputy Sam Richardson. Berkeley County sheriff's deputies also aren't allowed to alter vehicles, said spokesman Dan Moon.

North Charleston police policy is not to allow alteration of a vehicle unless approved by the police chief, said spokesman Spencer Pryor. In Pryor's 10 years, it's never been requested, he said.

Former Charleston police chief Reuben Greenberg allowed personalized plates, but later changed his mind after complaints. Plates now can be personalized only with prior approval.

The line between appropriate and inappropriate use of tax-paid resources gets stretched repeatedly in the state, from governors' use of security and state vehicles to questions about whether local police officers should be allowed to drive vehicles to homes out of jurisdiction.

Summerville has been here before. The town was sued in 1997 over a candidate for the state Senate taping a campaign commercial that featured the then-public safety director in the fire station with firefighters. A federal judge threw out the suit because the plaintiff failed to show that any federal law was broken.

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