WASHINGTON — Two influential House Democrats called on Monday for two officials at the Department of Homeland Security’s independent watchdog to testify to Congress about the agency’s handling of missing Secret Service text messages from the day of the Jan. 6 attack on the Capitol, accusing their office of engaging in a cover-up.
In a letter sent Monday to Joseph V. Cuffari, the agency’s inspector general, the heads of two congressional committees said they had developed “grave new concerns over your lack of transparency and independence, which appear to be jeopardizing the integrity of a crucial investigation run by your office.”
The letter from Representative Carolyn B. Maloney, Democrat of New York and the chairwoman of the Oversight Committee, and Representative Bennie Thompson, Democrat of Mississippi and the chairman of the Homeland Security Committee, renewed a demand the pair made last week that Mr. Cuffari step aside from the investigation. It also called for two of his office’s top employees to testify this month.
The inspector general’s office did not immediately respond to a request for comment.
It was the latest turn in a drama over what became of text messages sent and received by Secret Service agents around the time of the Capitol riot.
Mr. Cuffari last month informed the House committee investigating the Jan. 6 attack that the messages had been erased, suggesting that it occurred as part of a device replacement program, and that the department had ceased looking into what became of them because they were the subject of a criminal investigation. He has said those whose messages were missing included agents who were part of former President Donald J. Trump’s security detail.
In the letter on Monday, Ms. Maloney and Mr. Thompson, who also leads the Jan. 6 panel, wrote that their committees had obtained “new evidence” that Mr. Cuffari’s office had “secretly abandoned efforts to collect text messages from the Secret Service more than a year ago.” They added that his office “may have taken steps to cover up the extent of missing records, raising further concerns about your ability to independently and effectively perform your duties as inspector general.”
The lawmakers’ letter cited reporting from CNN that the inspector general learned in May 2021 — seven months earlier than previously revealed — that the Secret Service was missing critical text messages.
The letter also stated that the committees had learned that Mr. Cuffari’s office was notified in February that text messages from Chad Wolf and Kenneth T. Cuccinelli II, the top two political officials at the Department of Homeland Security on Jan. 6, 2021, could not be accessed. They added that the inspector general was also aware that Mr. Cuccinelli was using his personal phone and also failed to collect messages from that device.
Mr. Wolf was the acting secretary at the department, and Mr. Cuccinelli was his deputy. Their missing texts were reported earlier by The Washington Post.
Mr. Wolf wrote on Twitter that he “complied with all data retention laws and returned all my equipment fully loaded to the Department. Full stop. DHS has all my texts, emails, phone logs, schedules, etc. Any issues with missing data needs to be addressed to DHS.”
Since then, the lawmakers have raised questions about not just the missing text messages but why Mr. Cuffari did not alert Congress sooner or take steps to retrieve them earlier.
The committees obtained a July 27, 2021, email from Thomas Kait, a deputy inspector general, stating that “we no longer request phone records and text messages from the USSS relating to the events on January 6th.” He used the abbreviation for the United States Secret Service.
The lawmakers also said their panels had gathered evidence that it was not until four months later, on Dec. 3, 2021, that the inspector general finally submitted a new request to the department for certain text messages.
Mr. Kait, they said, removed key language from a February 2022 memo that highlighted the importance of the text messages and criticized the department for failing to comply with the Dec. 3, 2021, request.
Ms. Maloney and Mr. Thompson called on Mr. Kait and Kristen Fredricks, the office’s chief of staff, to sit for transcribed interviews by Aug. 15.
Mr. Cuffari prompted a firestorm on Capitol Hill last month when he reported that the text messages had been erased, even after he had requested them as part of an inquiry into the events of Jan. 6.
The Secret Service disputed parts of the inspector general’s findings, saying that it “lost” data on “some phones” as part of a preplanned three-month “system migration” in January 2021, but insisting that no texts pertinent to the inquiry “had been lost in the migration.” The agency said that the project was underway before it received notice from the inspector general to preserve its data, and that it did not “maliciously” delete text messages.
In response, the Jan. 6 committee issued a subpoena to the Secret Service seeking text messages from Jan. 5 and 6, 2021, that were said to have been erased, as well as any after-action reports.
The Secret Service said it might not be able to recover a batch of erased text messages from phones used by its agents around the time of the attack on the Capitol last year, but had delivered “thousands of pages of documents” and other records related to decisions made on Jan. 6.
Representative Jamie Raskin, Democrat of Maryland and a member of the Jan. 6 committee, said it appeared that the inspector general “was extremely tardy in reporting this egregious situation for a long time.”
“It’s getting to the point where inspectors general need inspectors general,” he said. “It just seems like a scandalous dereliction of duty on his part.”