Of all the expanded investigative powers authorized by Congress since the terror attacks of September 11, 2001, few have proved as controversial—or as consistent a source of embarrassment to federal law enforcement—as National Security Letters. Though audits by the Inspector General have uncovered widespread improprieties in the use of the investigative tool which allows the FBI to demand certain telecommunications and financial records without the need for a court order, a 2007 effort to further constrain NSLs stalled in committee.

Now, with a new administration and a sturdier Democratic majority in place, Rep. Jerrold Nadler (D-NY) and Rep. Jeff Flake (R-AZ) on Monday reintroduced the National Security Letters Reform Act. The bill would significantly tighten the rules for NSLs—which can currently be used to obtain records "relevant" to an investigation, whether or not they pertain to someone even suspected of wrongdoing—and the gag orders that typically accompany them.

NSLs are not new, but their scope and prevalence were greatly expanded by the USA PATRIOT Act of 2007. In 2000, investigators issued some 8,500 NSL, according to a report by the Office of the Inspector General. In 2006—the last year for which figures were available, the number had risen to at least 49,425, down from a peak of at least 56,507—though no estimates are available for 2001 or 2002, and sloppy record-keeping found by the OIG means all figures are lowbound. The "overwhelming majority" of those are for phone or telecommunications records, and by 2006, the bulk of those for which a target's nationality was specified were issued in connection with investigations of US persons.

The FBI hasn't coped terribly well with the increased volume: those OIG reports found an NSL process riddled with errors and policy violations—some of which appeared to have been flatly illegal. Agents sent "exigent letters" claiming an emergency when none existed, claimed grand jury subpoenas were pending when they weren't, and in some instances obtained information to which the statute did not entitle them. At hearings in 2007, a visibly angry Rep. Dan Lungren (R-CA), who had supported expanding NSL authority, said the OIG's findings sounded more appropriate to "a report about a first- or second-grade class" than college-educated FBI agents. Thus far, however FBI officials have successfully argued that they are aware of the problems and have already begun implementing reforms to prevent future errors.

Since Nadler and Flake last sought to supplement those internal efforts with more robust statutory checks, federal appellate courts have added to the list of rationales for congressional action. Civil libertarians have attacked not only NSLs themselves, but the broad gag provisions typically attached to them, which prevent parties served with them from discussing the requests. Congress sought to mollify critics by modifying the PATRIOT Act in 2006 to permit NSL recipients to retain attorneys and challenge orders they regard as unreasonable. But late last year, the Second Circuit Court of Appeals ruled that the law still gave FBI officials too much power to silence speech, with court oversight too anemic to satisfy the First Amendment. The court was prepared to allow a mix of court reinterpretation and FBI policy to bring the review procedures up to constitutional muster, but also invited Congress to fix the defective provision.

The National Security Letters Reform Act would do that, and a good deal more. While it would still permit high-ranking FBI officials to issue NSLs with temporary gag orders attached, the Bureau would have to petition a judge in order to extend that order beyond an initial 30 days. Instead of requiring NSL recipients to challenge such orders, showing there was "no reason" to think disclosure might harm public safety or the integrity of an investigation, the agency would have the burden of showing a court specific facts justifying each six-month extension of the gag.

Perhaps most significantly, however, the law would radically narrow the scope of National Security Letters, which can currently be used to obtain financial or telecommunications transaction records that an FBI agent asserts are "relevant" to an ongoing investigation. Under the Nadler-Flake bill, NSLs would have to certify that the target to whom the information sought pertained was believed, on the basis of "specific and articulable facts," to be a "foreign power or agent of a foreign power."

The bill also establishes strict "minimization" requirements, mandating the destruction of any wrongly obtained information. While intelligence agencies often rely on "minimization" to protect the privacy of US persons, this often means only that innocent information will be retained without being indexed in a log or database for the relevant case. Anyone whose records are obtained via an NSL without adequate factual basis, or in violation of the statutory restrictions, is entitled to sue the person responsible for issuing the letter, to the tune of $50,000.