“It was a mistake to rely on written responses by the president,” Schiff said during an appearance on ABC’s “This Week” on Sunday. “That’s generally more what the lawyer has to say than what the individual has to say.”

Rep. Adam Schiff (D-Calif.), chairman of the House intelligence committee, said he believes special counsel Robert Mueller made “a mistake” by not interviewing President Donald Trump under oath as part of his Russia investigation.

NEW: Rep. Adam Schiff says "it was a mistake to rely on written responses" by Trump in the Mueller probe. "I can certainly understand why the lawyers like Giuliani were fighting this" because Trump "seems pathologically incapable of telling the truth" https://t.co/P6iz1j1VA4 pic.twitter.com/E4bN9NEewC

Trump’s legal team submitted the president’s written answers to the special counsel’s questions in November, but refused to allow him to be interviewed by Mueller, claiming it could be a “perjury trap.”

Rudy Giuliani, Trump’s personal attorney and the former mayor of New York City, has repeatedly claimed the president wanted to sit down with Mueller for an interview, but that his legal counsel advised him against doing so.

“I could certainly understand why the lawyers like Giuliani were fighting this, because the president is someone who seems pathologically incapable of telling the truth for long periods of time,” Schiff said Sunday.

He continued: “Nonetheless, if you really do want the truth, you need to put people under oath, and that should have been done. But the special counsel may have made the decision that, as he could not indict a sitting president on the obstruction issue, as it would draw out his investigation, that that didn’t make sense.”

Mueller submitted his final report on the yearslong investigation into Russian interference in the 2016 election to Attorney General William Barr on Friday. Barr is expected to send his key findings from the report to Congress as early as Sunday.

Mueller’s team will not recommend any further indictments arising from the probe, a Justice Department official said Friday, though other federal prosecutors are continuing to investigate some aspects of Trump’s campaign and business dealings.