FBI's Carnivore a picky eater

For all the controversy over the FBI's e-mail surveillance system, it turns

out that Carnivore is a picky eater and not a devourer of data, according

to bureau officials.

The system was shown off at bureau headquarters in Washington, D.C.,

Friday, and bureau officials and others will testify about Carnivore today

before the House Judiciary Committee's Constitution Subcommittee.

The subcommittee wants to discuss concerns that applying the new technology

violates statutes protecting citizens from unreasonable searches and seizures.

Criticism of Carnivore has made strange bedfellows since word of it

became public this month, with a core of Republican leaders and the American

Civil Liberties Union expressing concern over the technology's potential

for abuse by the law enforcement community.

But the system is not new and is not a secret, officials said. The FBI

has been using the system for about three years and has briefed government

and industry leaders about it, bureau officials said.

In some cases, the Carnivore system, developed by the bureau, has not

even been fielded for e-mail taps. Instead, Internet service providers,

some of which have their own sophisticated monitors, have provided the bureau

with information under court order, FBI officials said.

The officials, who provided the Carnivore demonstration on condition

of anonymity, said the standards guiding the tapping of e-mail are the same

as those for traditional telephone wiretaps. However, Carnivore can be so

narrowly focused that extraneous information — such as personal conversations

by people other than the subject of an investigation — is not collected.

At the briefing, a laptop computer stood in for a small, stackable computer

that would normally be deployed for an Internet tap. Its color screen showed

a menu that agents would use to target an e-mail account.

Agents target e-mail in much the same way a computer user would define

a search of a database or document — by describing what to look for and

what not to look for. As the search criteria is keyed in, the data takes

the shape of a pyramid on its side as it narrows in on e-mail specifically

targeted by officials and spelled out in a court order authorizing the tap.

As an ISP transmits e-mail, Carnivore copies those messages with the

targeted individual's ISP number — the equivialent of a phone number — and

sends it through a filter that retains on tape or disk only those e-mail

messages meeting the criteria programmed by agents into Carnivore.

In most cases, FBI officials said, the information plucked from e-mail

messages consists of the "To" and "From" identification and does not even

include the subject line. But the FBI can and has intercepted e-mail messages

in their entirety, officials acknowledged.