What do voter ID laws say?
They require that all citizens must present certain kinds of identification when they turn up at the voting booth. Until relatively recently, only a handful of states had such rules. But since 2011, 13 mostly Republican-controlled states, including Texas and Wisconsin, have introduced laws demanding voters provide photo ID, such as a driver's license or a passport. Eleven of those state laws will be in place for November's midterm elections. A fierce legal battle is now underway between the laws' defenders, who say they'll prevent voter fraud, and the Obama administration and civil rights groups, which argue the restrictions are designed to discourage some groups from voting. "A great democracy," said former President Bill Clinton, "does not make it harder to vote than to buy an assault weapon."

Why do civil rights groups oppose the laws?
They say they discriminate against low-income and minority voters — groups that tend to vote Democratic. About 25 percent of eligible black voters and 16 percent of Hispanic voters don't have photo ID, compared with 9 percent of whites, according to the Brennan Center for Justice at New York University. The center says many poor voters can't afford cars or vacations abroad, and thus don't have driver's licenses or passports, and will be unfairly burdened by the $75-and-up cost of obtaining birth certificates and traveling to a government agency to secure a photo ID. In a recent opinion condemning Wisconsin's voter ID law, U.S. Circuit Judge Richard Posner — a President Reagan appointee — compared the laws to the poll tax implemented to stop blacks from voting in the Jim Crow–era South. The only reason to impose voter ID laws, said Posner, "is to discourage voting by persons likely to vote against the party responsible for imposing the burdens."

What do Republicans say?
In 2012, Mike Turzai, Republican majority leader in Pennsylvania's House, boasted that strict new voting laws would "allow Governor Romney to win" the state. Republicans disavowed those comments when they became public, though the conservative group True the Vote has claimed that Democrats routinely drop off busloads of illegal voters at polling places throughout the country. No evidence has ever been supplied to support that claim, but advocates say ID laws are needed to buttress public confidence in elections, arguing that voting should require the same proof of identity as, say, buying an airplane ticket. "It only makes sense that when you show up to vote," said Pennsylvania state Rep. Daryl Metcalfe, "that you prove you are who you claim."

Is election fraud a big problem?
The available evidence indicates that it's not. In 2007, a five-year Justice Department review found virtually no proof of organized attempts to skew elections. Earlier this year, a study by Loyola Law School in Los Angeles discovered just 31 credible instances of voter impersonation among the approximately 1 billion ballots cast in all U.S. elections since 2000. Cases of voter ID fraud are extremely rare, experts say, because it would be almost impossible to swing an election by organizing hundreds or thousands of bogus voters to go to the polls under assumed identities. "You can't steal an election one person at a time," said Robert Brandon, president of the Fair Elections Legal Network. "You can by stuffing ballot boxes — but voter IDs won't stop that."

Do the laws have any impact on turnout?
During the 2012 election, polling analyst Nate Silver estimated that strict voter ID laws would reduce turnout up to 2.4 percent. That margin could easily make a difference in the outcome of a close election. But it's difficult to quantify the laws' effect, since studies often rely on what people say about why they did or didn't vote, and such self-reporting isn't reliable. Separating the impact of ID requirements from other factors affecting voting also poses a problem. In Georgia, for instance, black voter turnout actually rose 44 points from 2006, the year voter ID laws were introduced in the state, to 2010 — but that might have been because then–presidential candidate Barack Obama pushed the black vote up everywhere in 2008.

How will the ID laws affect the midterms?
They could make Election Day a mess, thanks to a recent series of conflicting court decisions. In Arkansas, the state Supreme Court last week struck down a photo ID bill, meaning it won't be in effect in November. In Texas, an appeals court overruled a federal judge and reintroduced the state's ID law. The Supreme Court last week allowed the law to stand for the upcoming midterms, but earlier this month it temporarily blocked Wisconsin's strict ID requirements. Some officials fear this flurry of rulings will leave voters and poll workers unsure about what types of ID are required, meaning some eligible voters could be turned away at the polls or just decide to stay home. "The new voter suppression," says Nina Turner, Democratic candidate for Ohio secretary of state, "is all this voter confusion."

A tough ID law in Texas
Of all the country's voting laws, the Lone Star State's has received the most headlines. Texas implemented the law last year just hours after the Supreme Court struck down Section 5 of the Voting Rights Act, which required states with a history of discrimination to seek approval from the Department of Justice before making changes to voting regulations. Only certain types of state-issued photo ID are now accepted: Concealed-weapons permits are valid, but student IDs are not. Texans can apply for "free" election ID cards but have to pay for the official documents that are needed to apply for the cards; a copy of a birth certificate can cost anywhere from $2 to $47. Because many Texas counties have no ID-issuing office, some rural residents have to travel 100 miles to the nearest location. Of the estimated 608,470 registered voters who lack the correct ID, 279 had obtained free ID cards by September.