While clearing the F.B.I. of acting out of political bias, the Justice Department’s independent inspector general, Michael E. Horowitz, and his team uncovered a staggeringly dysfunctional and error-ridden process in how the F.B.I. went about obtaining and renewing court permission under the Foreign Intelligence Surveillance Act, or FISA, to wiretap Carter Page, a former Trump campaign adviser.
…Most of those targets never learn that their privacy has been invaded, but some are sent to prison on the basis of evidence derived from the surveillance. And unlike in ordinary criminal wiretap cases, defendants are not permitted to see what investigators told the court about them to obtain permission to eavesdrop on their calls and emails.
Civil libertarians for years have called the surveillance court a rubber stamp because it only rarely rejects wiretap applications.
…Everyone involved in the Page wiretap knew that what they were working on was likely to come under close scrutiny, yet they still repeatedly failed to follow policies.
Mr. Horowitz also said senior-level supervisors bore responsibility for permitting systemic failures to fester, and his office has begun a broader audit of unrelated FISA applications.
…The government has fought hard to keep outsiders from seeing what goes into its FISA applications. In 2014, a federal judge in Illinois ordered the government to show a defense lawyer classified materials about the national security surveillance of his client, which would have been the first time a defense lawyer had been given such materials since Congress enacted FISA in 1978.
But the Obama administration appealed, and an appeals court overturned the order, agreeing that letting the defense counsel see the application would create an intolerable risk of disclosing sensitive government secrets.
That stands in contrast to how wiretapping works in ordinary criminal law. Targets are usually told when the surveillance ends. If they are prosecuted based on evidence gathered from the wiretap, they get to see what was in the application so their defense lawyers can argue that the government made a mistake and the evidence should be suppressed.
The prospect of that adversarial second-guessing gives criminal investigators a reason to be scrupulous about what they put into their requests for wiretaps.