A federal court has struck down a Texas law requiring voters to present photo identification at the ballot box in the second ruling this week to effectively accuse the state of racial discrimination and attempting to manipulate elections.

In an escalating legal battle between mostly Republican-controlled states and the Obama administration over voter ID and other election laws, a panel of three judges in Washington DC found that the Texas legislation imposed "strict, unforgiving burdens on the poor" because of the cost and process involved in obtaining identification. The US justice department told the court that voters would have to pay for birth certificates and travel up to 250 miles to obtain ID cards. The court said this imposed a "heavy burden" on any voter and would be "especially daunting for the working poor" who are more likely to be racial minorities. The court concluded that if the law was implemented it "will likely have a retrogressive effect" by limiting access to the ballot box. It said that evidence submitted by Texas in support of its claim that the law was not discriminatory – and was necessary to combat voter fraud – was "unpersuasive, invalid, or both". The US justice department told the court there are 600,000 people registered to vote in Texas whose names are not on driving licence or state identification databases. It said the voter ID laws in Texas and other states is a blatant attempt to disenfranchise African American and Hispanic voters. On Tuesday another federal court ruled that an attempt by Texas to redraw its electoral maps was illegal because it was intended to diminish the impact of the Latino vote. In both cases, the justice department blocked the laws as in breach of the 1965 Voting Rights Act, which requires those states with a history of systematic racial discrimination to seek approval from Washington for changes to electoral legislation and procedures. Rick Perry, the Texas governor, decried Thursday's ruling. "Chalk up another victory for fraud. Today, federal judges subverted the will of the people of Texas and undermined our effort to ensure fair and accurate elections. The Obama administration's claim that it's a burden to present a photo ID to vote simply defies common sense," he said. But the US attorney general, Eric Holder, who has described voter ID legislation as an attempt to roll back some of the gains of the civil rights era by disenfranchising minorities, said the ruling was a victory for civil rights. "The court's decision today and the decision earlier this week on the Texas redistricting plans not only reaffirm – but help protect – the vital role the voting rights act plays in our society to ensure that every American has the right to vote and to have that vote counted," he said.

"The justice department's efforts to uphold and enforce voting rights will remain aggressive and even-handed. When a jurisdiction meets its burden of proving that a proposed voting change would not have a racially discriminatory purpose or effect, the department will not oppose that change. When a jurisdiction fails to meet that burden, we will object."

The Texas attorney general, Greg Abbott, said he will take the issue to the supreme court, which has already endorsed the right of states to require photo IDs at the ballot box under certain conditions. "The supreme court of the United States has already upheld voter ID laws as a constitutional method of ensuring integrity at the ballot box. Today's decision is wrong on the law and improperly prevents Texas from implementing the same type of ballot integrity safeguards that are employed by Georgia and Indiana and were upheld by the supreme court," Abbott said. As the judges issued their verdict in the Texas case, another court nearby was hearing a challenge from South Carolina to the justice department's blocking of its voter ID law in December. South Carolina said that it will issue identification cards free to those who do not have a driving licence, passport or other approved document. The justice department says there is still a cost involved as individuals must buy a birth certificate, if they do not already have one, in order to obtain the free ID. Critics say that the claim by South Carolina, Texas and others that voter fraud is a serious problem is not borne out, because there have been very few prosecutions. They say the Texas legislation, passed by a Republican-controlled state legislature with Perry's support is intended to discourage black and Latino voters who are more likely to support the Democratic party. Eight states have passed voter identification laws over the past year. Holder told a conference in May that there is a "growing need to protect the voting rights of every eligible citizen" amid a flurry of legislation and executive orders by state legislatures and governors. The meeting was told the laws are intended to prevent African Americans in particular from voting because nearly one in four black people lack photo identification. "In my travels across this country I've heard a consistent drumbeat of concern from citizens who for the first time in their lives now have reason to believe that we are failing to live up to one of our nation's most noble ideals and some of the achievements that defined the civil rights movement now hang, again, in the balance." Some critics see the legal challenge by Texas and other states as a co-ordinated attempt to kill off at least parts of the voting rights act as outdated. In May, Alabama challenged the validity of the legislation over a justice department block on the redrawing of constituency boundaries. A US appeals court said in rejecting Alabama's case that the implementation of the voting rights act is legitimate because it is intended to stop racially motivated disenfranchisement which he called "one of the greatest evils".