The 2014 election is about more than just the campaigns for the House, Senate and state offices: it's the first national election since a wave of controversial new voter ID laws were introduced. It will be a huge test case for the how those restrictions will impact voting in America and perhaps for the future of these rapidly expanding laws.

Voter ID laws are often premised on stopping voter fraud, despite the fact that this crime is is vanishingly rare. They're so restrictive that they've inspired comparisons to "modern day Jim Crow," and when you look at the effect of the laws on minority communities, it becomes clear that that's not a totally unreasonable description.

Here's what you need to know about how voter ID laws work, and why their impact on people of color and other groups puts them near the top of the list of modern-day civil rights concerns.

1. What's the big deal with asking someone to present their ID in order to vote?

There's been a recent rise in state laws that require voters to present some form of identification, such as a driver's license or passport, at the polls in order to vote. (These are different from "non-documentary" identification requirements, which let voters verify their identity in other ways, like by signing an affidavit or poll book, or by providing their address or birth date.)

To see the rise in these laws, compare the percentage of states that required photo ID in 2000, the the percentage that require it in 2014:

These expanding voter ID laws represent more than just a hassle. To put it simply, they make voting a lot harder, and have become a growing civil rights concern.

The groups most often affected by voter ID requirements are the same ones that tend to vote Democratic, so there's a clear partisan element. But even more troubling than their impact on electoral outcomes is the who they tend to keep from the ballot box: disproportionately people of color. In that way, the effect of the laws is often seen as another iteration of a decades-long political fight in the US over race and civil rights.

2. Which Americans are most impacted by voter ID requirements?

People who don't have or can't obtain the identification required by voter ID laws are, more often than not, racial minorities, elderly, or poor.

That's a big part of what makes voter ID laws so controversial. It's not just that they'll have an immediate impact on the election, but that legislation targeting these groups can look like the latest iteration of a long American history of using voting restrictions to keep certain people away from the ballot box.

To be clear, it's by no means an official part of the GOP party platform, nor the stated rationale for most voting restrictions, to restrict specific demographic groups from voting. Still, it is statistically true that lower-income Americans and people of color are more likely be restricted — and that these groups are more likely to vote for Democrats, meaning that the voting ID laws just happen to help Republicans in elections.

It's not just critics of voter ID laws who make this connection; sometimes Republicans point it out themselves. In 2012, Pennsylvania House Majority Leader Mike Turzai, a Republican, bragged that the voter ID law he'd helped pass was "gonna allow Governor Romney to win the state of Pennsylvania." On this and other occasions, individual Republicans have said that they know voter ID laws keep a group of people who are more likely to be Democrats from voting.

The fact is that the laws, in execution, have a demonstrably disparate impact on racial minority groups. This effect, along with the political debate about the laws, carry echoes of America before the Voting Rights Act of 1965, when outrageous election laws, from poll taxes to literacy tests, were designed specifically to keep African-Americans from the ballot.

3. What's the evidence that voter ID laws stop people from voting?

A full 11 percent of voting-age US citizens — about 21 million people — don't have a government-issued photo ID. That means, in states that have strict photo ID laws, they can't vote.

Racial minorities are disproportionately likely to lack photo ID and make up a big part of that 21 million. Fully 25 percent of African Americans of voting age (compared to only 8 percent of their white counterparts) don't have a photo ID.

Voter ID laws also have a disproportionate impact on low-income Americans, who are less likely to have driver's licenses or to be able to afford a form of identification, which can also be used as ID. According to a September 2014 Government Accountability Office report, fees for driver's licenses range from $14.50 to $58.50. These are not huge fees, but they're certainly significant if money is tight. Even for those who could afford it if they stretched, $50 price tag on voting could be enough to dissuade them, which is its own form of voting restriction.

The numbers don't lie: tightening restrictions on voter ID has the effect of making voting much tougher for these demographic groups. And so they vote less.

4. Why are voting rights such a big political issue right now?

The fight over voting rights — a highly partisan battle over how voting ought to work and which regulations are needed to make sure voting is accessible and fair — began heating up after the 2010 midterm elections. It was then, two years after high turnout among people of color famously helped to win the presidency for Barack Obama, that many state legislatures with new Republican majorities passed laws establishing a multitude of new voting restrictions, including requirements for identification.

Things got much worse in 2013, when the Supreme Court, in the case Shelby County v. Holder, struck down part of the Voting Rights Act of 1965. The Supreme Court's majority based this in part because on their assessment that the current conditions surrounding racial discrimination in voting were not as bad as they were when the law had been passed.

Historically, most of the legal battles over voter ID laws have involved the Voting Rights Act, which was designed to make it harder to pass state and local laws that made it difficult or impossible for African Americans to vote, during a time when lawmakers went to extreme lengths to do this.

When that law was gutted in 2013, it led to a virtual free-for all of restrictive voting legislation. Many states rushed to pass voter ID laws, sparking public debates about their effects, as well as legal challenges. Election laws that restrict voting for racial minority groups are still sometimes challenged in court, post-Shelby, but with considerably less success

5. Don't we need voter ID laws to stop voter fraud?

Voter fraud — any illegal tampering with the results of an election — is something you'll hear about frequently from people who support voter ID laws. But statistics show that voter fraud is extremely rare.

Supporters of voter ID laws tend to argue that voter fraud is a serious threat to democracy and to Americans' confidence in the election process. For example, the authors of a 2014 Heritage Foundation publication, "Does Your Vote Count?," assert that election fraud has been a serious problem throughout US history, in support of the position that "Photo IDs should be required for both in-person voting and absentee balloting."

However, in-person voter fraud, the kind that would be combatted by requiring identification at the polls, is exceedingly rare. The American Civil Liberty Union concludes, "There is no credible evidence that in-person impersonation voter fraud — the only type of fraud that photo IDs could prevent — is even a minor problem."

Justin Levitt, a professor at the Loyola University School of Law, tracked "any specific, credible allegation that someone may have pretended to be someone else at the polls, in any way that an ID law could fix," in the context of general, primary, special, and municipal elections from 2000 through 2014. He found just 31 incidents between 2000 and August 2014. Only 31 incidents of voter fraud in the entire country over 14 years! The U.S. Government Accountability Office concluded in a September 2014 report that "few instances of in-person voter fraud" have been documented, citing studies that calculate a rate of voter fraud between 0.1 percent and zero percent.

Meanwhile, voter ID laws stand to disenfranchise many more people than voter fraud impacts. A September Government Accountability Office report indicated that nearly 100,000 fewer people voted in Kansas and Tennessee thanks to the introduction of voter ID laws in those states. (No surprise: younger voters and black voters took the biggest hit.)

6. What's the voter ID law in my state?

Most states (34 of them) have laws requiring voters to show some form of identification at the polls, and the majority (31) of these voter identification laws are currently in force.

The three that have passed but aren't in force are Pennsylvania's law, which has been struck down and will not be appealed; North Carolina's law, which will go into effect in 2016; and Wisconsin's law, which the Supreme Court has blocked from being implemented, pending the outcome of a legal challenge.

Voter ID laws vary from state-to-state. Some require photo identification (like a driver's license or military ID), while others accept forms of non-photo identification (such as a bank statement).

The laws also differ when it comes to how strict they are – meaning, what happens to voters who can't produce the requested ID. States with strict voter ID laws require voters who don't have ID to vote with a provisional ballot and then take additional steps after Election Day (for example, returning to the election office with an ID) to ensure that their votes are counted. States with less strict voter ID laws may let a person vote if he or she signs an affidavit certifying identity, or may allow election workers to verify whether the person was registered, without the voter having to take any further action.

This map, created by the National Conference of State Legislatures, shows the national landscape of voter ID laws.