Top Democrats in Congress on Friday demanded a full investigation of the Justice Department’s extraordinary decision to secretly seize data from the accounts of at least two House lawmakers and their aides as the Trump administration sought to hunt down the source of leaks of classified information.
Democrats and free speech advocates decried the seizures and aggressive investigative tactics, first reported by The New York Times on Thursday, as a gross abuse of power to target another branch of government and said the pursuit of information on some of former President Donald J. Trump’s most visible political adversaries smacked of dangerous politicization.
They called variously for the Justice Department inspector general and Congress itself to open an inquiry — and for department personnel involved in the investigation to be fired.
“I hope every prosecutor who was involved in this is thrown out of the department,” Representative Eric Swalwell of California, one of at least two Democrats on the Intelligence Committee whose records were seized, said in an interview. “It crosses the line of what we do in this country.”
“We have to figure out what and how it happened to determine the extent to which D.O.J. misused its powers under Trump for political purposes,” he continued. “I think it was absolutely a frontal assault on the independence of a coequal branch of government.”
The Times reported that as it hunted for the source of leaks about Trump associates and Russia, the Justice Department had used grand jury subpoenas to compel Apple and one other service provider to hand over data tied to at least a dozen people associated with the committee beginning in 2017 and 2018. The department then secured a gag order to keep it secret.
In addition to Mr. Swalwell, investigators gained access to the records of Representative Adam B. Schiff of California, the top Democrat on the committee and now its chairman, committee staff and family members, including one who was a minor.
Though leak investigations are routine, current and former officials at the Justice Department and in Congress said seizing data on lawmakers is nearly unheard-of outside of corruption investigations.
In the Senate, Ron Wyden, Democrat of Oregon and a member of the Intelligence Committee who has been a leading critic of government surveillance, said he planned to introduce legislation trying to crack down on the use of gag orders like the one used on Apple and news organizations, which were also scrutinized in the leak investigation.
“Revelations about the Trump Justice Department’s targeting of journalists and political rivals proves again how surveillance powers can be abused and the need to put strict limits on gag orders that prevent the targets of this spying from learning about it for years,” Mr. Wyden said in a statement.
While top House Democrats, including Mr. Schiff and Speaker Nancy Pelosi, focused on the need for an inspector general investigation, Senator Brian Schatz, Democrat of Hawaii, said Congress should conduct its own inquiry.
“I respectfully ask the House to not call for investigations from the executive branch, but rather to do it themselves,” he wrote on Twitter, noting the Senate could try but had fewer tools available to compel answers.