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Attorney General Eric Holder went off script today to say that voter ID laws like one being implemented in Texas are "poll taxes," equating the requirement that voters show a state-issued photo ID in order to cast ballots to the Jim Crow laws of the early 1900s.

"Many of those without IDs would have to travel great distances to get them and some would struggle to pay for the documents they might need to obtain them," Holder said in a speech to the NAACP on Tuesday, referring specifically to a law being implemented in Texas. "We call those poll taxes."

The Supreme Court ruled that poll taxes were unconstitutional in 1937 and the 24th Amendment, ratified in 1964 outlaws poll taxes in federal elections.

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Holder's "poll tax" comment was not in the prepared remarks which were given to the press and came while Holder was decrying the Texas voter ID law that the Justice Department is currently challenging in federal court.

Holder said Texas' law would be "harmful to minority voters" because while just 8 percent of white Americans do not have a valid ID, 25 percent of African Americans lack the required ID.

"Especially in recent months, Texas has - in many ways - been at the center of our national debate about voting rights issues," Holder said. "Let me be clear: we will not allow political pretexts to disenfranchise American citizens of their most precious right."