<span>Photograph: Nicholas Kamm/AFP/Getty Images</span>
Photograph: Nicholas Kamm/AFP/Getty Images

Donald Trump conceded in his court filing that he didn't retain official government documents, as the former president argued that some of the documents collected by the FBI could be subject to executive privilege.

The former president's lawyers submitted a motion on Monday arguing that a special master should be appointed to determine what evidence the justice department can review.

The National Archives should have been given the documents that are subject to executive privilege because they are not authorized to be kept by Trump.

The book says that the Mar-a-Lago stay saved Giuliani from drinking and depression.

One of the criminal statutes listed on the warrant used by the FBI to search the former president's Mar-a-Lago resort appeared to be conceded by the motion.

A former FBI agent and former associate dean at Yale Law School said that if he acknowledges that he is in possession of documents that could have a colorable claim of executive privilege, those should be at the National Archives.

He admits in the filing that he is in possession of them, which is what the government is trying to establish.

If the justice department wanted to use the communications seized by the FBI for furtherance of a crime, it should not do so.

The presidential records act had no enforcement mechanism, even as they conceded that the justice department might pursue the privilege argument as a tacit admission.

The motion could throw up more challenges for the former president, as it lays out a months-long battle by the justice department to recover certain records in a pattern of interactions that could be construed as obstruction of justice.

It was not clear if the obstruction listed in the search warrant for Mar-a-Lago was related to the investigation into retrieving government documents from Mar-a-Lago or something else.

The justice department took multiple steps to retrieve 15 boxes in January, additional materials in June, and then 26 boxes when the FBI searched them.

One day after the National Archives told Trump's lawyers that the boxes contained classified documents, they accepted service of a grand jury subpoena.

Despite taking custody of documents responsive to the subpoena, the justice department learned there may have been more documents marked as classified, and issued a subpoena for security camera footage of the hallway outside where the materials were being stored.

The justice department did not think Trump was being completely honest or forthcoming in his interactions with the investigation, according to the subpoena for security tapes.

When the government retrieved materials from Mar-a-Lago in June, the custodian of Trump's records said they had given back documents responsive to the subpoena, only for the FBI to get more boxes of classified materials.

Two weeks after the FBI search took place, there was a late filing of the motion.

The motion was not filed in West Palm Beach. The judge has no knowledge of the underlying affidavit and could rule in such a way to reveal to Trump if he or his lawyers are suspected of obstruction.