Former President Donald Trump has pleaded not guilty to federal charges alleging he hoarded classified documents detailing sensitive military secrets and schemed to thwart government efforts to get them back.Trump appeared before a judge in Miami’s federal courthouse on Tuesday in a stunning moment in American history days after he became the first former president charged with federal crimes.But about a thousand miles away, part of Trump’s defense is well underway in a different venue — the halls of Congress.That's where Republicans have been preparing for months to wage an aggressive counteroffensive against the Justice Department."Where is the discussion about a sitting president that his justice department just indicted his top candidate that is going to run against him in less than two years?" said Republican House Speaker Kevin McCarthy.The federal indictment against Trump unsealed Friday includes 37 counts, including allegations that the former president intentionally possessed classified documents, showed them off to visitors, willfully defied Justice Department demands to return them and made false statements about them.The Republican campaign to discredit federal prosecutors skims over the substance of those charges, which were brought by a grand jury in Florida. GOP lawmakers are instead working, as they have for several years, to foster a broader argument that law enforcement — and President Joe Biden — are conspiring against the former president and possible Republican nominee for president in 2024."I think if you look at polling, most Republicans believe that what's happening to President Trump is one-sided. The Hunter Biden fiasco has been going on for four years. Other people have had classified information in their personal residences," said Republican Senator Lindsey Graham of South Carolina.To press their case, Trump’s backers are citing the Justice Department’s decision in 2016 not to bring charges against former Secretary of State Hillary Clinton, his Democratic opponent in that year’s presidential race, over her handling of classified information.His supporters also are invoking a separate classified documents investigation concerning President Joe Biden to allege a two-tier system of justice that is punishing Trump, the undisputed early front-runner for the GOP’s 2024 White House nomination, for conduct that Democrats have engaged in."When you deal with Pence, Biden, Clinton, there was no willful concealment of official classified records. In (Trump's) case... the indictment spelled out in detail that there was alleged willful concealment over a longer period of time. And completely different cases," said Democratic Senator Dick Durbin of Illinois.The White House disclosed in January that, two months earlier, a lawyer for Biden had located what it said was a “small number” of classified documents from his time as vice president during a search of the Washington office space of Biden’s former institute. The documents were turned over to the Justice Department.Lawyers for Biden subsequently located an additional batch of classified documents at Biden’s home in Wilmington, Delaware, and the FBI found even more during a voluntary search of the property.The revelations were a humbling setback for Biden’s efforts to draw a clear contrast between his handling of sensitive information and Trump’s. Even so, as with Clinton, there are significant differences in the matters.Though Attorney General Merrick Garland in January named a second special counsel to investigate the Biden documents, no charges have been brought and, so far at least, no evidence has emerged to suggest that anyone intentionally moved classified documents or tried to impede the FBI from recovering them.