Debates about abortion. Controversy over the Confederate flag. Repeated phrases open to different interpretations. Forget political candidates for a moment. Ordinary Americans have a lot on their plates.
Their license plates, that is.
Renewed furor over "Choose Life" taglines - the source of fierce legal fights ever since they were first approved in Florida in 1999 - is again raising First Amendment concerns.
It also highlights a broader trend, some experts say. In an election-year climate of heightened opinionism, the use of "specialty plates," which gained traction in the 1980s as a form of college boosterism, now tilts toward the institutionalizing of a bumper-sticker culture. A growing number of partnerships among state governments and private organizations seek to turn license plates into miniature mobile billboards.
"These plates are a measure of intensity of opinion," says Adam Berinsky, an assistant professor of politics at the Massachusetts Institute of Technology in Cambridge. If more people are paying to air their political beliefs, he adds, that "could be a sign of increased intensity and interest in politics."
It's not purely politics. Specialty plates are meant to inform fellow motorists of a driver's affinity for manatees, disdain for drugs, loyalty to an alma mater, or neatly encapsulated position on some other issue.
The optional taglines carry an extra cost, which benefits the state and the sponsoring organization, be it the Sons of Confederate Veterans or a group promoting literacy.
"We're really moving away from the two-color, alphanumeric situation," says Melissa Savage, transportation expert at the National Conference of State Legislatures in Denver.
A national total of specialty-plate programs has not been pinned down, says Ms. Savage. But during seven years spent watching states confer about plate policies, she has seen an increasing amount of energy expended - even before plate-design teams set to work.
It's a statutory traffic jam.
"Some states require that new legislation be passed every time they start a new special-plate program," says Savage. Illinois, for example, has a statute for each of more than 200 different plate options, she says. "And then you have other states where there's very little legislative oversight, and this is more an administrative response."
There has been a judicial response, as well. Last month in Tennessee, a federal judge ruled that plates bearing the antiabortion slogan - proceeds benefit nonprofit adoption services - were unconstitutional in that they promoted one side of a debate, and so represented viewpoint discrimination.
That's an especially egregious form of discrimination, says David Hudson, research attorney at the First Amendment Center at Vanderbilt University in Nashville, Tenn.
Without offering an alternative view, Mr. Hudson says, the state was judged to have crossed a little-understood line from an area of somewhat defensible speech restriction to one that leaves them open to attack.
"An example of content discrimination would be a city law that prohibits any speech of a political nature in a public park," he explains. Such a law would allow people to speak on religious topics, for example, but not political ones. "A viewpoint-discrimination law would be [one] that prohibited the Green Party from speaking in the park, but allow Democrats to speak there."
In the Tennessee Choose Life case, in fact, one abortion-rights group suggested that only a plate advancing its cause would level the field. In a widely reported legal response, legal scholar Michael Dorf tried to put that demand in perspective.
"The fact that Tennessee produces license plates that urge the public to preserve and protect Great Smoky Mountains National Park without also producing plates urging the destruction of this natural haven," Mr. Dorf wrote, "should not count as a violation of the First Amendment."
The plate debate is complicated by other components of First Amendment law, says Hudson. "The government will argue for the government-speech doctrine," he says, "[and] that it is engaging in its own [protected] speech and can advocate certain messages, such as 'stop smoking,' or 'drive safely.' "
So what makes states willing to wade into the legal crossfire on behalf of what Morris Fiorina, professor of political science at Stanford University, calls a "relatively small population of extreme partisans"?
"It's a moneymaker," says Savage. Each state has a different way of printing and distributing plates. But the cost of making a license plate can be as little as 80 cents, she says, and speciality-plate costs include a fee of at least $25, often much more, on top of standard charges.
Not even standard state slogans have been free of dispute. A New Hampshire couple's bid to cover up "Live Free or Die" made it to the US Supreme Court 25 years ago. They won on the grounds that it was "compelled speech."
At least one state - Wyoming - steers clear by keeping it simple. "Let me see here," says a staffer at the Laramie County treasurer's office in Cheyenne, which issues plates. "If it's a truck, it says 'truck' on it."
Wyoming drivers out to make a statement have but one option. Supervisor Janet Fridline takes the phone and sums up with a reference to the bucking-bronco silhouette that adorns the state plate: "We have the horse."