WASHINGTON — The first prosecution arising from the Benghazi attacks is playing out in the federal courthouse blocks from both the White House and Capitol Hill, an appropriate setting for a case that has drawn stark lines between President Barack Obama and Republicans in Congress. The criminal proceedings could provide new insights into the 2012 attacks that killed four Americans and will serve as the latest test of the US legal system's ability to handle terrorism suspects captured overseas. Unfolding during an election year, the case against alleged mastermind Ahmed Abu Khattala could also help shape the legacies of Obama and Attorney General Eric Holder, and spill over into the potential 2016 presidential candidacy of Hillary Rodham Clinton. Even as the court case slogs forward, it may be challenging for the public to untangle the law from the politics, given how prominent the attacks on the diplomatic compound in the eastern Libyan city have become in US political discourse. “What's going to matter to the public more than anything else is the result, and I think it's going to only diffuse some of the ongoing Benghazi conspiracy theories if the Obama administration is going to be able to successfully obtain a conviction in this case,” said American University law professor Stephen Vladeck, a national security law expert. Still, he said, the case raises the same legal issues as past terrorism prosecutions and should not by itself be viewed as a referendum on the Obama administration. “The story of this case is not the story of the Obama administration's reaction to Benghazi,” he added. “The story of this case is those who were responsible for Benghazi and those who need to be held accountable for the four deaths that resulted.” A 10-minute court appearance amid tight security Saturday was the American public's first concrete sense of Abu Khatalla, the Libyan militant accused by the US government of being a ringleader of the fiery assault on Sept. 11, 2012. US special forces captured him in Libya during a nighttime raid two weeks ago, and he was transported to the US aboard a Navy ship, where he was interrogated by federal agents. He was flown by military helicopter to Washington. Prosecutors have yet to reveal details about their case, with a two-page indictment unsealed Saturday offering no new details. Abu Khattala pleaded not guilty to a single terrorism conspiracy charge punishable by up to life in prison, but the Justice Department expects to bring additional charges soon that may be more substantial and carry more dire penalties. A three-count criminal complaint filed last year and unsealed after his capture charged Abu Khattala with killing a person during an attack on a federal facility — a crime that carries the death penalty. – AP