Lawyers for Donald Trump have asked a federal judge to throw out the indictment charging him with retaining classified documents at his Mar-a-Lago club on grounds of presidential immunity, claiming they were his to keep because he designated them personal records while he was president. The decision to designate the documents as personal records under the Presidential Records Act meant it was an official act of his presidency for which he could not face prosecution, his lawyers wrote in the 22-page filing. “President Trump’s decision to designate records as personal and cause them to be removed from the White House plainly constitutes an official act within the ‘outer perimeter’ of the president’s official duties,” the filing said. Classified information is material owned by the United States and cannot, by definition, be personal. Trump’s request to toss the charges amounted to an extraordinary interpretation of presidential power that would allow presidents to use national security secrets as they liked when they left office, legal experts suggested. It also marked the latest explanation from Trump about why he was justified in retaining classified documents. Previously, during the criminal investigation, Trump suggested documents were automatically declassified when he took them to the White House residence or that he could declassify using his mind. The presidential immunity claim was one of several filings Trump submitted on Thursday seeking to throw out the Espionage Act charges brought by the special counsel Jack Smith. Trump also argued, among other things, his retention of a document about US nuclear weaponry should be thrown out because his “Q” clearance had not yet been cancelled. Trump’s motion to dismiss was certain to result in a high-stakes battle with prosecutors before the presiding US district judge Aileen Cannon, if only because the idea that a president cannot be held accountable for actions undertaken in office remains unresolved. The argument about the Q clearance could also face an uphill struggle as it was only granted to Trump for use during his presidency, and there has been no evidence it was to be continued after he left office. Moreover, clearances alone do not permit storage of classified materials outside of special facilities. The presidential immunity claim that Trump made in the classified documents case was similar in scope to the presidential immunity claim that Trump made in Washington, where he is seeking to dismiss charges that he plotted to overturn the 2020 election and stop the peaceful transfer of power. The matter remains unresolved in Washington because Trump has appealed the immunity claim to the US supreme court, which has not decided yet whether to hear the argument. By making a similar immunity claim in the classified documents case, which is being prosecuted in Florida, a different jurisdiction and appeals circuit to Washington, Trump may have now forced the supreme court to take up the case, so it can maintain uniformity on the law. How quickly the court moves on the immunity claim stemming from the Washington case was already being closely watched, since it could affect when Trump might go to trial: an expedited process could mean a trial as early as May, while a slow process could mean a trial after the 2024 election. Trump’s overarching legal strategy in all of his criminal cases has apparently been to seek delay, in the hopes that winning a second presidency would allow him to install a loyal attorney general who would drop the charges, or if convicted, to issue himself a self-pardon. The Trump legal team settled on filing an immunity claim in Washington because it was perhaps the only motion that he could litigate pre-trial – virtually every other complaint must be contested after trial – and crucially, with immunity, it automatically put the case on pause. As a result of his immunity motion working its way through the appeals process, Trump managed to force the federal judge in Washington to cancel the scheduled 4 March trial date. Trump might now also be able to have his May trial date in Florida cancelled by repurposing the same tactic.