WASHINGTON — A legal battle between Texas and the Justice Department over the state’s new voter ID law opened in federal court Monday, as lawyers for the state argued that the law does not violate the federal Voting Rights Act.

A 2011 law passed by Texas’ GOP-dominated Legislature requires voters to show photo identification when they head to the polls.

In opening arguments, lawyers for the state said the law represents the will of the people. The Justice Department contends that the law runs afoul of the federal act passed in 1965 to ensure minorities’ right to vote.

‘‘Texas Democrats, like their national counterparts, have been wholly out of step with their constituents,’’ said Adam Mortara, a lawyer representing Texas. ‘‘Voters want photo ID.’’

Mortara said the state’s new statute is in line with similar laws that have cleared legal challenges in Indiana and Georgia. He also said the federal government would not be able to prove that any voters — and particularly minority voters — would be hindered by the law.

‘‘It’s really quite difficult to find anyone who’s registered to vote who doesn’t already have a photo ID,’’ he said.

Lawyers for the Justice Department strongly disputed the Texas position.

Elizabeth Westfall, in her opening for the department, said the evidence would show that as many as 1.4 million voters lack any form of acceptable identification under Texas’ new law. She also stressed that Texas would not be able to prove there was no intent to discriminate against minority voters when it passed the law.

‘‘Texas will be unable to meet its burden,’’ she said.

Westfall noted the law was passed in the Texas Legislature under ‘‘the uniform objection’’ of minority lawmakers and that the Justice Department would show evidence it does discriminate against minority voters.

‘‘We look forward to explaining the flaws in the state’s argument,’’ she said.

The opening statements set up a case that will test the limits of the Voting Rights Act. The Obama administration blocked Texas’ voter ID law in March, citing the act. Texas, in turn, filed a lawsuit against the Justice Department, sending the case to federal court in Washington.

A three-judge panel will decide whether Texas’ law passes legal muster. The trial is expected to last five days.

Testimony from witnesses began immediately after opening statements, with Texas calling Brian Keith Ingram, an official with the Texas secretary of state’s office. Ingram told the court he knew of at least four verified instances when someone voted who had recently passed away and said there could be as many as 239 such instances.

‘‘It’s more common than we thought, and it is troubling,’’ he said.

Under cross examination, Ingram said that there is a possibility some of those instances are the result of clerical errors.

The trial marks the second time in months that Texas and the Justice Department have argued in Washington over the Voting Rights Act.

In January, the two sides spent two weeks arguing in front of a similar three-judge panel about Texas’ redrawn congressional maps. No final decision has been made in that case, but a federal court has approved interim maps that have allowed Texas elections to go ahead.

Many of the key players in that case have returned for this one. As in January, Mortara is serving as one of Texas’ lead attorneys and several Justice Department lawyers who worked on that trial are working on this one. One of the judges in this week’s trial — Rosemary Collyer, appointed in 2002 by George W. Bush — is also involved in both cases.

The other judges hearing the voter ID case are David Tatel, appointed by Bill Clinton in 1994, and Robert Wilkins, appointed in 2010 by President Obama.

Since 2010, at least 10 states, including Texas, have passed laws requiring people to show a government-issued photo identification card when they go to the polls.

Supporters of voter ID laws, including many conservative Republicans, contend they are necessary to protect against voter fraud. But opponents say instances of such voter fraud are extremely rare and that voter ID laws could suppress turnout among the elderly, poor, and some racial minorities who are less likely to have driver’s licenses or passports and who might find it harder to miss work or lose pay to obtain proper ID.

In Houston on Monday, the head of the NAACP likened the group’s fight against conservative-backed voter ID laws to the great civil rights battles of the 1960s.

Benjamin Todd Jealous, the CEO and president of the National Association for the Advancement of Colored People, said these are ‘‘Selma and Montgomery times,’’ referring to historic Alabama civil rights confrontations. He challenged those attending the NAACP’s annual convention to redouble their efforts to get out the vote in November.

‘‘We must overwhelm the rising tide of voting suppression with the high tide of registration and mobilization and motivation and protection,’’ he said.

‘‘The NAACP will never stand by as any state tries to encode discrimination into law,’’ Jealous said.

The weeklong convention will include an appearance by Attorney General Eric Holder, which was postponed from Monday until Tuesday. Republican presidential nominee Mitt Romney and Vice President Joe Biden were also expected to speak later in the week.