Covering Their Tracks, contd.

Cavicchia had been using the account to communicate with online criminals. "You have to be crafty to deal with informants," Frazzini says. "They can't very well communicate with you on your Secret Service e-mail account." But, he says, Cavicchia also was receiving documents mailed by the Secret Service.

Ethics began monitoring Cavicchia, collecting Secret Service documents and recording Cavicchia's T-Mobile chat sessions. There he learned that at least one Shadowcrew member's ICQ number was under surveillance.

Frazzini says it's an indication of "the cat-and-mouse game" that is part of the underworld of cyberspace. "It's like rats running around out there," he says. "And they got him."

T-Mobile spokesman Peter Dobrow says the company had been working with the Secret Service since October 2003 to identify the hacker.

Jacobsen pleaded guilty in February to one count of unauthorized access to a protected computer and recklessly causing damage. His sentencing is scheduled for May 16. His plea agreement has been sealed by the government, and his attorney, Greg Wesley of the Federal Public Defender's office in Los Angeles, will not discuss his case.

But the Secret Service had made its way up the Shadowcrew organization chart—with its informant placed high in the hierarchy. That helped trap Ethics, according to the affidavit against Jacobsen.

Tipped to the existence of the Secret Service documents by a Shadowcrew member, the informant got Ethics to confirm that he was the individual who had found the documents in Cavicchia's T-Mobile account. And the rats ran around again.

A few days later, Ethics asked the informant for a proxy server so he could "browse and log in to a site with the credentials of a USSS Agent." The informant provided a server controlled by the Service's Newark field office. So, the Secret Service was able to track Ethics tracking Cavicchia.