Judge Aileen Cannon suspended a key deadline in former President Donald Trump’s classified documents case amid defense allegations that prosecutors failed to preserve critical evidence in the case.

Trump’s defense team had asked the judge last month to suspend the May 9 deadline for expert disclosures and Classified Information Procedures Act notice until three weeks after the conclusion of the New York hush money trial. This week, Cannon temporarily stayed the deadlines. The latest delay could make going to trial this year more difficult.

Trump’s attorneys also alleged that prosecutors “failed to maintain the integrity of the contents of at least some of the boxes obtained from Mar-a-Lago.” The case against Trump hinges on the documents in the those boxes.

“It is likely that President Trump will file additional motions for sanctions based on spoliation, including a motion to dismiss the charges if the [Special Counsel’s] Office cannot prove in a reliable way how it seized and handled the key evidence in the case, which will be a central issue at any trial,” defense attorneys wrote in a reply.

Trump has pleaded not guilty to 40 felony counts that allege he kept sensitive military documents, shared them with people who didn’t have security clearance, and tried to get around the government’s attempts to get them back.

Trump has repeatedly said that the civil and criminal charges he faces are the result of politically motivated prosecutions designed to keep him from returning to the White House.

Trump is gearing up for a rematch in November with President Joe Biden.