Trump lawyers say Mar-a-Lago boxes contained foreign leader briefings

New letter sent to Congress attempts to paint Trump's retention of classified-marked documents at Florida home as inadvertent

Donald Trump's lawyers in the Mar-a-Lago documents investigation found the 15 boxes the former president returned to the National Archives a year after the end of his presidency mostly contained briefings for calls with foreign leaders, according to a new letter they sent to Congress.

The majority of the letter - seen by the Guardian and earlier reported by CNN - served to characterize Trump's retention of classified-marked documents as inadvertent, and due to White House staffers sweeping all documents into boxes during a chaotic departure at the end of the administration.