WASHINGTON — A chastened F.B.I. told a secretive court on Friday that it was increasing training and oversight for officials who work on national security wiretap applications in response to problems uncovered by a scathing inspector general report last month about botched surveillance targeting a former Trump campaign adviser.
In a rare unclassified and public filing before the court that oversees wiretapping under the Foreign Intelligence Surveillance Act, or FISA, the F.B.I. also said it would extend its overhaul to requests for orders permitting it to collect logs of its targets’ communications and other business records — not just wiretaps of the contents of phone calls and emails.
“The F.B.I. has the utmost respect for this court and deeply regrets the errors and omission identified by” the inspector general, wrote the F.BI. director, Christopher A. Wray, in a statement included with the filing. He called the conduct described by the report “unacceptable and unrepresentative of the F.B.I. as an institution.”
Under FISA — a law for surveillance aimed at monitoring suspected spies and terrorists, as opposed to ordinary criminals — the government must convince a judge that an American is probably an agent of a foreign power. Because the FISA court hears only from the government, and what it says is never shown to defense lawyers, the Justice Department says it has a duty to be candid and tell judges every relevant fact in its possession.
But the Justice Department’s inspector general, Michael E. Horowitz, uncovered that the F.B.I. had cherry-picked and misstated evidence about the Trump adviser, Carter Page, when seeking permission to wiretap him in October 2016 and in 2017 renewal applications. At the same time, Mr. Horowitz determined that the opening of the Russia investigation was legal and found no politicized conspiracy against President Trump by high-level F.B.I. officials.
The problems included omitting details that made Mr. Page look less suspicious. For example, the court was not told that Mr. Page had said to a confidential informant in August 2016 that he had no interactions with Paul Manafort, Mr. Trump’s former campaign manager, even though the F.B.I. suspected Mr. Page might be a conduit between Russia and Mr. Manafort.
The court was also not told that Mr. Page had told the C.I.A. about his contacts with Russians over the years, a fact that made that pattern of contacts look less suspicious. The Justice Department, passing on the factual portrait it received from the F.B.I., had pointed the judges to that pattern as a reason to think that he might be a Russian agent.
Mr. Horowitz said he did not find documentary or testimonial evidence that the F.B.I. officials responsible for compiling the relevant evidence about Mr. Page for the court were politically biased against Mr. Trump. But he rejected as unsatisfactory their explanations that they were busy on other aspects of the Russia investigation.
In a response appended to the inspector general report last month, Mr. Wray had already announced that he would make changes aimed at ensuring that the bureau put forward a more comprehensive portrait of the facts about targets when preparing wiretap applications.
The new filing, which detailed 12 steps, like enhancing checklists for preparing filings, added granular detail. It came in response to an unusual public order last month. Rosemary M. Collyer, then the presiding judge on FISA court, ordered the F.B.I. to propose fixes to its process by Jan. 10 to ensure the problems would not recur.
“The frequency with which representations made by F.B.I. personnel turned out to be unsupported or contradicted by information in their possession, and with which they withheld information detrimental to their case, calls into question whether information contained in other F.B.I. applications is reliable,” Judge Collyer wrote.
On Jan. 1, Judge James E. Boasberg took over Judge Collyer’s role on the FISA court. He will now have to evaluate whether the proposed changes are sufficient to restore the judges’ confidence in the factual affidavits F.B.I. officials submit or if more is necessary.
It is not clear whether Judge Boasberg will take such potential steps as appointing a “friend of the court” to critique the F.B.I.’s proposal before he issues any order.
The chairman of the Senate Judiciary Committee, Senator Lindsey Graham, Republican of South Carolina, has said he wants to impose new checks and balances on the F.B.I.’s national security surveillance powers, at least when investigations touch on political campaigns, in legislation his panel may take up after Mr. Trump’s impeachment trial.
In his statement with the court filing on Friday, Mr. Wray called FISA an “indispensable tool for national security investigations” and pledged to work to ensure the accuracy and completeness of FISA applications “in recognition of our duty of candor to the court and our responsibilities to the American people.”