NEW YORK (AP) — Documents with classified markings were discovered in former Vice President Mike Pence ’s Indiana residence last week, his lawyer says, the latest in a string of recoveries of papers meant to be treated with utmost sensitivity from the homes of current and former top U.S. officials.

“A small number of documents,” taken into FBI custody last Thursday, “were inadvertently boxed and transported” to the former vice president’s home at the end of the last administration, Pence’s lawyer, Greg Jacob, wrote in a letter to the National Archives shared with The Associated Press.

He said that Pence had been “unaware of the existence of sensitive or classified documents at his personal residence” until a search last week and that he “understands the high importance of protecting sensitive and classified information” and stands ready to cooperate with “any appropriate inquiry.”

The revelation came as the Department of Justice was already investigating the discovery of documents with classification markings in President Joe Biden’s home in Delaware and his former Washington office, as well as former President Donald Trump’s Florida estate. Democrat Biden has indicated he will seek reelection, Republican Trump is already a declared candidate, and Pence has been exploring a possible 2024 campaign that would put him in direct competition against Trump, his former boss.

The newest discovery thrusts Pence, who had previously insisted that he followed stringent protocols regarding classified documents, into the debate over the handling of secret materials by officials who have served in the highest ranks of government.

Trump is currently under criminal investigation after roughly 300 documents with classified markings, including at the top secret level, were discovered at his Mar-a-Lago. Officials are trying to determine whether Trump or anyone else should be charged with illegal possession of those records or with trying to obstruct the months-long criminal investigation. Biden is also subject to a special counsel investigation after classified documents from his time as a senator and in the Obama administration were found at his properties.

Trump, who denies any wrongdoing, reacted to the new development on his social media site: “Mike Pence is an innocent man. He never did anything knowingly dishonest in his life. Leave him alone!!!” Trump and Pence have clashed over Pence’s refusal to go along with Trump’s efforts to overturn the results of the 2020 election.

While a very different case, the Pence development could bolster the arguments of Trump and Biden, who have sought to downplay the significance of the discoveries at their homes. The presence of secret documents at all three men’s residences further underscores the federal government’s unwieldy system for storing and protecting the millions of classified documents it produces every year.

Pence’s lawyer, Jacob, said in his letter that the former vice president had “engaged outside counsel, with experience in handling classified documents” to review records stored at his home on Jan. 16 “out of an abundance of caution” amid the uproar over the discovery of documents at Biden’s home.

Jacob said the Pence documents with classification markings were immediately secured in a locked safe. FBI agents visited the residence the night of Jan. 19 at 9:30 p.m. to collect the documents that had been secured, according to a follow-up letter from the lawyer dated Jan. 22. Pence was in Washington for an event at the time.

A total of four boxes containing copies of administration papers —- two in which “a small number” of papers bearing classified markings were found, and two containing “courtesy copies of vice presidential papers” — were discovered, according to the letter. Arrangements were made to deliver those boxes to the National Archives Monday.

Congressional leaders were notified of the discovery by Pence’s team on Tuesday.

The boxes, according to a Pence aide, were not kept in a secure location, but were taped shut and were not believed to have been opened since they were packed. The former vice president’s staff also searched the Washington office of his advocacy group last week and did not discover additional documents, according to the person, who spoke on condition of anonymity because of the sensitive nature of the search.

Material found in the boxes came mostly from Pence’s Naval Observatory vice presidential residence, the packing of which would not have been handled by the vice president’s office or its lawyers. Other material came from a West Wing office drawer, the person said.

The National Archives declined to comment on the discovery. A Justice Department spokesman also declined to comment, and a lawyer for Pence did not immediately respond to an email seeking elaboration.

Pence told the Associated Press in August that he did not take any classified information with him when he left office.

Asked directly if he had retained any such information, he said, “No, not to my knowledge.”

In an interview this month with Fox Business, Pence described a “very formal process” used by his office to handle classified information as well as the steps taken by his lawyers to ensure none was taken with him.

“Before we left the White House, the attorneys on my staff went through all the documents at both the White House and our offices there and at the vice president’s residence to ensure that any documents that needed to be turned over to the National Archives, including classified documents, were turned over. So we went through a very careful process in that regard,” Pence said.

On Capitol Hill, members of the Senate intelligence committee expressed incredulity over the mishandling of documents by top U.S. officials.

Republican Sen. John Cornyn of Texas noted that classified documents are only moved out of the committee’s offices in locked bags.

“In my book, it’s never permissible to take classified documents outside of a secure facility” except by a secure means of transport between such facilities, he said.

House Intelligence Chairman Mike Turner, a Republican, said he planned to request a formal intelligence review and damage assessment.

And Republican Sen. Rick Scott of Florida, another potential 2024 candidate, said, “I don’t know how anybody ends up with classified documents. … I mean, every classified document I’ve ever seen has a big ‘Classified’ on it.”

Sen. Ron Wyden, D-Ore., and a senior member of the Senate Intelligence Committee, pointed to broader concerns with the classification system, complaining that it “is at the point where there is so much out there it is hard to determine what ought to be classified, and then it is hard to determine what should be declassified.”

Meanwhile, some Republicans pressed for a search of former President Barack Obama’s personal records.

An Obama spokesperson referred to a 2022 statement from the National Archives that said the agency took control of all of his records after he left office and “is not aware of any missing boxes of presidential records from the Obama administration.”

Representatives of former presidents George W. Bush and Bill Clinton and former Vice President Dick Cheney said all of their classified records had been turned over to NARA upon leaving the White House.

Mike Pompeo, who served as Trump’s secretary of state and is mulling his own 2024 GOP presidential bid, told the AP in August that he had not taken any any classified material with him after leaving the administration.

But he told Fox News channel Tuesday, “When you’re in the executive branch, you have these documents in your home. One can imagine a note getting someplace, getting stuck. I suspect that may be what happened.”

Copyright 2023 by the Associated Press.  All Rights Reserved.

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