The Justice Department’s inspector general revealed Tuesday that in each of more than two dozen cases his office reviewed, the FBI routinely failed to document evidence for claims made in secret surveillance court requests.

The significant findings indicate problems extend beyond those identified last year by the office of IG Michael Horowitz, which concluded that FBI agents had made significant errors and omissions in applications to eavesdrop on a former Trump campaign adviser during the early months of the Russia investigation.

The disclosure is also likely to embolden civil libertarians in both political parties who are pushing for major reform of the Foreign Intelligence Surveillance Act.

Horowitz launched the review after finding in a December report that the FBI improperly withheld information from the Foreign Intelligence Surveillance Court when seeking surveillance orders against 2016 Trump campaign adviser Carter Page.

Horowitz’s office reviewed 29 cases involving US residents between 2014 and 2019 and found insufficient documentation in every case to support claims in court papers.

The FISA court is a shadowy body able to authorize surveillance of US citizens and others suspected of terrorism or espionage. But it hears only from government attorneys, heightening the stakes if presentations are incomplete.

According to an investigation summary released by Horowitz, the inspector general’s team reviewed 29 FISA cases, and in four cases, there was no “Woods File,” a term for a required set of evidence to support each fact alleged in FISA requests.

In the other 25 cases, Horowitz’s team found “apparent errors or inadequately supported facts in all of the 25 applications.”

“Interviews to date with available agents or supervisors in field offices generally have confirmed the issues we identified,” Horowitz wrote. He added: “As a result of our audit work to date and as described below, we do not have confidence that the FBI has executed its Woods Procedures in compliance with FBI policy.”

In an FBI response, Associate Deputy Director Paul Abbate said the bureau already took corrective action last year. Forms documenting FISA application facts “must now be scanned and maintained in the electronic case file,” he wrote.

This month Congress let three provisions of FISA expire after a clash over how to restrain authorities, who say the current system is essential to preventing terrorism.

Since Edward Snowden’s 2013 leaks, libertarian and conservative Republicans and left-wing Democrats pushed FISA reforms such as a ban on “back door” searches of files on US citizens, but generally are blocked by an equally bipartisan alliance of centrists and party leaders. In a notable exception, Congress in 2015 ended the dragnet collection of US call records.

In 2018, Trump signed an extension of Section 702 of FISA, which allows authorities to collect and store vast swaths of internet traffic.