Attorneys for President Donald Trump’s former campaign chairman Paul Manafort denied in a court filing unsealed Tuesday that he “intentionally” lied to investigators with special counsel Robert Mueller’s office.

The filing came about a month after prosecutors accused Manafort of making false statements. His attorneys said Tuesday that their client didn’t mean to mislead authorities, framing some of the government’s allegations as little more than misinterpretations of Manafort’s answers and others as a simple lack of recall on Manafort’s part.

“Often (after being shown or told about relevant documents or other evidence) [Manafort] corrected himself or clarified his responses,” his attorneys said, a fact that they argued “does not support a determination that he intentionally lied.”

“It is not uncommon … for a witness to have only a vague recollection about events that occurred years prior and then to recall additional details about those events when his or her recollection is refreshed with relevant documents,” Manafort’s attorneys said. “Similarly, cooperating witnesses often fail to have complete and accurate recall of detailed facts regarding specific meetings, email communications, travel itineraries and other events.”

His lawyers said it should come as no surprise that Manafort couldn’t recall details he was purported to have lied about, since “these occurrences happened during a period when Mr. Manafort was managing a U.S. presidential campaign and had countless meetings, email communications and other interactions with many different individuals, and traveled frequently.”

Further, defense attorneys said the government identified no patterns to Manafort’s alleged lies.

Manafort agreed in September to cooperate with authorities while pleading guilty to charges of conspiracy against the United States and conspiracy to obstruct justice through witness tampering.

His attorneys said Tuesday that Manafort has been kept in solitary confinement for his own safety. He’s turned over access to his electronic devices and email accounts as part of his cooperation.

Defense attorneys added that Manafort has suffered severe gout for several months of his incarceration that has sometimes been severe enough to require that he use a wheelchair.

“He also suffers from depression and anxiety and, due to the facilities visitation regulations, has had very little contact with his family,” his attorneys said.

A judge has ordered prosecutors to provide evidence to support the statements in dispute by Jan. 14.