Earlier this year, the New York Times reported that the FBI had revised its "Domestic Investigations and Operations Guide," which serves as a handbook for the bureau's 14,000 agents. The amended manual, which supersedes the original December 2008 edition, is one more step in the FBI's ongoing transformation since 9/11, as it morphs from a law enforcement agency into a domestic intelligence agency.

According to Kathleen Wright of the bureau's Washington, D.C., Office of Public Affairs, the new guide went into effect on Oct. 15.

The first version of the DIOG, which was controversial in its own right, allowed FBI agents to conduct surveillance, enlist informants and interview friends of suspects, all without a supervisor's approval. Many privacy advocates felt the wide-ranging surveillance powers it authorized would inevitably lead to abuses and have a negative effect on ethnic and religious minorities.

When the original DIOG was issued, Michael German, a former FBI agent and now an American Civil Liberties Union attorney, was quoted in the Washington Post as saying, "It is an extraordinarily broad grant of power to an agency that has not proven it uses its power in an appropriate manner."

The revised guide relaxes the rules even further, granting agents significantly broader powers, including the authority to administer lie detector tests, pick through people's household garbage and use surveillance teams to investigate "suspicious" individuals – all without a search warrant, the opening of a formal investigation, or even any concrete evidence of prior wrongdoing on the part of the "suspect." These procedures may be carried out under the lowest category of FBI inquiry, known as an "assessment."

It is important to note that even if the targeted individual or organization is found innocent, the information collected in the course of these assessments is nevertheless retained. Of the more than 82,000 assessments opened between March 2009 and March 2011, only 4 percent (3,315) were carried to the next level of investigation, leaving the information amassed on the other 96 percent (over 79,000) – who had been cleared of any misconduct – still available in the FBI's databases.

What these numbers tell us is that the overwhelming percentage of FBI assessments lead nowhere and therefore raise the concern that the bureau is casting far too wide a net with its investigatory procedures. Moreover, of those assessments that do become "preliminary" investigations, only a small percentage subsequently become "full" investigations, and of those that do, only a similarly small percentage result in criminal charges.

The original DIOG required agents to open an inquiry before searching a commercial or law-enforcement database for information on a particular individual. Under the new rules, agents may conduct database searches without even opening an assessment, so in the vast majority of cases – again, witness the great percentage of inquiries dropped for lack of incriminating findings – no record of these searches will exist.

This opens the door to potential abuses of power, making it more difficult to discover if an agent has improperly used one or more of these searches for personal reasons.

The new freewheeling database searches call to mind the FBI's earlier use of "national security letters," which permitted agents to obtain an individual's telephone records and other data without a search warrant, a practice that was curtailed in 2007 after an inspector general found it was commonly being misused.

In its centurylong history, the FBI has repeatedly tended to take on the role of a secret police. Two attorneys general – Harlan Fiske Stone in 1924 and Edward Levi in 1976 – found the bureau's widespread, covert surveillance and investigation of civilians to be so egregious that they issued guidelines aimed at checking these behaviors. Unfortunately, in both cases the guidelines were chipped away and eventually completely eroded over time.

Now, with the new "Domestic Investigations and Operations Guide," the bureau is inching uncomfortably close to once again taking on the role of a secret police. FBI spokesperson Wright maintains the new guide is "fine tuning, not any major change." But given the bureau's history, every incremental increase in FBI power must be regarded as portentous.

It is time for Attorney General Eric Holder to step forward and rein in the FBI, as his predecessors Stone and Levi did. For once, however, it would be good policy to check the bureau's power before the abuses spin out of control.

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Jay Feldman is a Davis author. His most recent book is "Manufacturing Hysteria: A History of Scapegoating, Surveillance, and Secrecy in Modern America."

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