The Justice Department under President-elect Donald Trump's first administration, during leak investigations, subpoenaed phone records from two lawmakers and 43 bipartisan congressional staffers who had access to classified information.
Records were obtained as prosecutors pursued investigations over leaks of classified information to media outlets in 2017 and 2018.
While the watchdog's investigation found no evidence of political motives, it concluded that "dozens of congressional staffers became part of the subject pool in a federal criminal investigation for doing nothing more than performing constitutionally authorized oversight of the executive branch."
Then-Reps. Adam Schiff, D-Calif., and Eric Swalwell, D-Calif., and Kash Patel, Trump's pick to lead the FBI in the incoming administration, were among those targeted, CNN reported.
The inspector general of the Biden administration's DOJ released a watchdog report Tuesday. Neither Patel, who was a staffer for the GOP-led House Intelligence Committee, nor the lawmakers were named in the report.
The report revealed prosecutors also sought records, including emails, from journalists at CNN, The Washington Post, and The New York Times.
The searches for records came not long after The Washington Post in July 2017 published a story about a meeting between Russia's then-ambassador to the United States Sergey I. Kislyak and Trump campaign adviser Jeff Sessions to discuss Trump's 2016 presidential campaign.
The article cited intelligence intercepts as a source of information to confirm the meeting took place.
No charges were brought in connection with the investigations, which the report found are now closed.
The report concluded that the subpoenas created at least the "appearance of inappropriate interference" by the DOJ into the work of Congress.
"[T]he decision to issue most of the compulsory process for their records was based on the close proximity in time between that access and the subsequent publication of the news articles," the inspector general wrote.
The report stated that while some protections for journalists exist, they were not properly followed. Also, there are no guardrails for prosecutors who want to subpoena communication records from members of Congress or their staff.
Reuters contributed to this story.