In the early 1990s, Russian mobsters partnered with Italian Mafia families in Newark, N.J., to skim millions of dollars in federal and New Jersey state gasoline and diesel taxes. Special Agent Larry Depew set up an undercover sting operation under the direction of Robert J. Chiaradio, a supervisor at the Federal Bureau of Investigation’s Washington, D.C., headquarters. Depew collected reams of evidence from wiretaps, interviews, and financial transactions over the course of two and a half years. Unfortunately, the FBI couldn’t provide him with a database program that would help organize the information, so Depew wrote one himself. He used it to trace relationships between telephone calls, meetings, surveillance, and interviews, but he could not import information from other investigations that might shed light on his own. So it wasn’t until Depew mentioned the name of a suspect to a colleague that he obtained a briefcase that his friend had been holding since 1989. “When I opened it up, it was a treasure trove of information about who’s involved in the conspiracy, including the Gambino family, the Genovese family, and the Russian components. It listed percentages of who got what, when people were supposed to pay, the number of gallons….