Senate Democratic leaders are demanding that Trump era attorneys general Bill Barr and Jeff Sessions give evidence about the secret seizure of data from House Democrats in 2018, calling it “shocking” and a “gross abuse of power”.

Senate majority leader Chuck Schumer and Illinois senator Dick Durbin said in a statement that Mr Barr and Mr Sessions “must testify before the Senate Judiciary Committee” and are subject to a subpoena if they refuse.

The demands came after Democratic representatives Adam Schiff and Eric Swalwell were notified that the Justice Department under Donald Trump seized their metadata from Apple three years ago.

The records of at least 12 people connected to the House Intelligence Committee were eventually shared by the company, including Mr Schiff, then the top Democrat on the committee and now its chairman.

Adam Schiff
Adam Schiff (J Scott Applewhite/AP)

While the Justice Department routinely investigates leaked information, including classified intelligence, opening such an investigation into members of Congress is extraordinarily rare. The disclosures reveal one branch of the government using its powers of investigation and prosecution to spy on another.

Mr Schiff said the seizures suggest “the weaponisation of law enforcement by a corrupt president”.

Apple informed the committee last month that the records had been shared and that the investigation had been closed, but did not give extensive detail. Also seized were the records of aides, former aides and family members, one of them a minor, according to the committee official.

The Justice Department obtained metadata — probably records of calls, texts and locations — but not other content from the devices, like photos, messages or emails, according to one of the people. Another said Apple complied with the subpoena, providing the information to the Justice Department, and did not immediately notify the members of Congress or the committee about the disclosure.

Eric Swalwell
Eric Swalwell, right (Manuel Balce Ceneta/AP)

The Trump administration’s attempt to secretly gain access to the data came as the then president was fuming publicly and privately over investigations — in Congress and by then special counsel Robert Mueller — into his campaign’s ties to Russia.

He called the probes a “witch hunt”, regularly criticised Democrats and Mr Mueller on Twitter and repeatedly dismissed as “fake news” leaks he found harmful to his agenda. As the investigations swirled around him, he demanded loyalty from a Justice Department he often regarded as his personal law firm.

Mr Schiff and Mr Swalwell were two of the most visible Democrats on the committee, then led by Republicans, during the Russia investigation.

Mr Schiff called for an investigation by the Justice Department’s inspector general on the seizures.

House speaker Nancy Pelosi said in a statement that the data seizures “appear to be yet another egregious assault on our democracy” by the former president.

“The news about the politicisation of the Trump administration Justice Department is harrowing,” she said.