Among the powers agents now have for an assessment:

• Conduct surveillance without an otherwise required court order

• Obtain grand jury subpoenas for personal telephone and e-mail accounts

• Recruit informants for feeding information about a group or person to the bureau

• Examine records maintained by federal, state and local government agencies, which are typically not accessible to the public, like police databases profiling past criminal suspects

In particular, the powers allow agents to "collect information relating to demonstration activities," according to the guidelines, for the purpose of protecting "public health and safety" before a major event, like the party conventions that occurred in St. Paul and Denver. The bureau can gather intelligence to determine where political demonstrators are lodging during the event, how they're traveling there, where demonstration activities are planned and how many people will attend, all without advanced proof that a national-security threat exists.

Agents can also access commercial databases containing large volumes of personal information on U.S. citizens, like those maintained by the private company ChoicePoint, which specializes in serving government agencies.

Here are the source documents:

• New FBI guidelines for investigations in full
• Memo discussing the changes distributed to Justice Department staffers (9/29)
• Testimony of FBI general counsel Valerie Caproni to the Senate Select Committee on Intelligence (9/23)
• Mueller Testimony: Senate Judiciary Committee (9/17)
• Mueller Testimony: House Judiciary Committee (9/16)
• Historical analysis of the guidelines by the Electronic Privacy Information Center