Court hears case on Texas voter ID law, ruling could impact other states In a case that could impact a string of states with strict voter ID laws, a federal court on Monday took up the tense dispute between Texas and the federal Department of Justice over that state's law requiring photo ID to cast a ballot. A three-judge panel in Washington, D.C., is hearing the case, which is scheduled to last five days. A ruling is expected by next month. The law, projected to impact hundreds of thousands of voters, was approved by the Republican-controlled state legislature to prevent voter fraud, then signed into law by Gov. Rick Perry. However, the Justice Department blocked the law this spring, saying it violates the Voting Rights Act of 1965 and unfairly impacts Hispanic and other minority voters -- who tend to vote Democratic. The federal law in part says states with a history of discriminatory laws need Justice Department approval before changing voter laws. Texas Attorney General Greg Abbott has said the law does not apply to the state's anti-fraud effort and that the Texas law is similar to those in Georgia and Indiana that have withstood legal scrutiny. Texas filed the suit with the expectation the Obama administration would attempt to have the law repealed. The Justice Department's evidence in the case is also being questioned. A data-collection agency Catalist, used by an expert witness for the administration, lists among its clients some of the country's most influential liberal groups including the Democratic House and Senate campaign committees, Planned Parenthood and the 2008 Obama campaign. House Judiciary Committee Chariman Lamar Smith, R-Texas, last week asked Attorney General Eric Holder why such a firm is providing the data. The panel's ruling will likely impact at least 15 other states - including Mississippi and South Carolina -- with similar legislation either having passed or pending. However, the final decision is expected to end up in the Supreme Court. "We'll do everything in our power to stand vigilant against any and all measures that threaten to undermine the effectiveness and integrity of our elections systems," Holder said Saturday in Las Vegas at the annual National Council of La Raza conference, a major political event for Hispanics.