WASHINGTON >> The Justice Department inspector general has found additional failures in the FBI’s handling of a secretive surveillance program that came under scrutiny after the Russia investigation, identifying problems with dozens of applications for wiretaps in national security investigations.

The audit results, announced today by Inspector General Michael Horowitz, suggest that FBI errors while eavesdropping on suspected spies and terrorists extend far beyond those made during the investigation into ties between Russia and the 2016 Trump campaign. They come as the FBI has scrambled to repair public confidence in how it uses its surveillance powers and as lawmakers uneasy about potential abuses have allowed certain of its tools to at least temporarily expire.

The new findings are on top of problems identified last year by the watchdog office, which concluded that the FBI had made significant errors and omissions in applications to eavesdrop on former Trump campaign adviser Carter Page during the early months of the Russia investigation. Those mistakes prompted internal changes within the FBI and spurred a congressional debate over whether the bureau’s surveillance tools should be reined in.

After the Russia report was submitted last December, Horowitz announced a broader audit of the FBI’s spy powers and the accuracy of its applications before the secretive Foreign Intelligence Surveillance Court.

The watchdog office selected for review a subset of applications in both counterterrorism and counterintelligence investigations covering the period from October 2014 to September 2019. It found problems in each of the more than two dozen applications it reviewed, including “apparent errors or inadequately supported facts.”

The audit examined how well the FBI was complying with internal rules that require agents to maintain a file of supporting documentation for every factual assertion they make in an application. Those rules, or “Woods Procedures,” were developed in 2001 with a goal of minimizing errors in the surveillance applications, known by the acronym FISA.

Horowitz said in a letter to FBI Director Chris Wray that in four of the 29 FISA applications his office selected for review, the FBI could not locate any of the supporting documentation that was supposed to have been produced at the time the application was submitted.

Each of the 25 other applications it reviewed contained “apparent errors or inadequately supported facts,” the inspector general said. In those instances, the facts stated in the applications were either not backed up any documentation or were inconsistent with the documentation.

The watchdog office said it found an average of about 20 issues per application, including one application with about 65 issues.

As a result, Horowitz wrote, “we do not have confidence that the FBI has executed its Woods Procedures in compliance with FBI policy, or that the process is working as it was intended to help achieve the ‘scrupulously accurate’ standard for FISA applications.”

The inspector general’s office did not make a judgment as to whether the mistakes it identified were “material” to the investigation or to the court’s decision to authorize the wiretaps.

The office recommended that the FBI “perform a physical inventory” to ensure supporting documentation exists for every application in all pending investigations. It also recommended that the FBI examine the results of “past and future accuracy reviews” so that it can identify trends and patterns and develop better training for agents.

The FBI and Justice Department say they have begun making significant changes, including additional training and other safeguards meant to ensure the accuracy of surveillance applications.

In a response letter, FBI Associate Deputy Director Paul Abbate said the FBI agreed with the office’s recommendations, and that the errors identified by the inspector general will be addressed by the more than 40 corrective actions that Wray ordered last year after the Russia probe report.

“As Director Wray has stressed, FISA is an indispensable tool to guard against national security threats, but we must ensure that these authorities are carefully exercised and that FISA applications are scrupulously accurate,” Abbate wrote.

The Justice Department said in a statement that it welcomes the audit, and that it has “been hard at work” implementing the changes demanded by Wray. Attorney General William Barr has also instituted his own changes, including in the handling of politically sensitive investigations.

“The Department is committed to putting the Inspector General’s recommendations into practice and to implementing reforms that will ensure that all FISA applications are complete and accurate,” the statement said.

The Foreign Intelligence Surveillance Court was established in 1978 to receive applications from the FBI to eavesdrop on people it suspects of being agents of a foreign power, such as potential spies or terrorists. Critics have long complained about the opaque, one-sided nature of the application process, and longstanding calls to overhaul the system received a bipartisan push because of the errors identified during the FBI’s investigation into ties between the Trump campaign and Russia.

The congressional debate tripped up FBI efforts to renew three surveillance provisions that expired this month, with lawmakers adjourning last week without agreeing on legislation that would renew the tools.

The Justice Department urged Congress today to revive the provisions as it continues working toward broader reforms.

“No one was more appalled than the Attorney General at the way the FISA process was abused. This abuse resulted in one of the greatest political travesties in American history and should never happen again,” Justice Department spokeswoman Kerri Kupec said in a statement.

“However,” she added, “FISA remains a critical tool to ensuring the safety and security of the American people, particularly when it comes to fighting terrorism.”

Republican Sen. Lindsey Graham, the chairman of the Senate Judiciary Committee, said he would ask Horowitz to appear before the panel to explain his findings.