This article is from the archive of our partner National Journal

This week marked the 50-year anniversary of "Bloody Sunday," the day hundreds of demonstrators in Selma, Alabama, were brutally beaten and arrested by state troopers as they attempted to march to Montgomery in a protest against racial discrimination in voter registration. Fifty years later, voting rights remain a hotly contested issue—especially where voter-identification laws are concerned.

Thirty-one states, mostly in the South, currently require voters to present identification on Election Day. These states maintain that this practice is important to prevent voter fraud, although research shows that fraud at the ballot box is rare. Others argue that requiring identification discriminates against those who can't afford the often-high costs of obtaining identification.

Speaking at the Edmund Pettus Bridge in Selma this past Saturday, President Obama said lawmakers should "pledge to make it their mission to restore" a section of the Voting Rights Act that was struck down by the Supreme Court in June 2013. The provision had allowed for closer federal regulation of voting laws in states with a history of racial discrimination. Senate Majority Leader Mitch McConnell said Sunday that Congress is "taking a look at" the landmark legislation.

Here's a look at the states that require identification at the polls and what the options are if getting that identification is not possible.

This article is from the archive of our partner National Journal.

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