During meetings with agents, Tripwire liaisons are given cards that explain what suspicious activity to look out for. Clancy says there’s nothing “earth shattering” on the cards, just commonsense things to be aware of, like customers purchasing large quantities of fertilizer or short lengths of pipe, stockpiling arms, or using cash for large transactions, among other things. The FBI also tells its Tripwire liaisons to talk to their customers, to ask questions, and to listen and observe their responses and to try to sense whether something is amiss. If an interaction or transaction seems unusual, Tripwire participants are told to call the nearest FBI Joint Terrorism Task Force (JTTF), the bureau’s counterterrorism investigative offices at 104 locations across the country.
Legitimate terrorism suspicions can also lead to other criminal activity, says Clancy, describing another Tripwire success from his time running a JTTF in Richmond, Virginia. In May 2010, a Home Depot that received Tripwire cards reported four individuals who came into the store and bought up the store’s supply of acetone, a common explosive precursor chemical. Then another suspicious activity report came from a nearby Lowe’s about the same individuals purchasing acetone. Then a smaller, privately owned hardware store called to report large acetone purchases as well as the individuals’ desire to purchase as much acetone as the store owner could get.
“We immediately set up a command post and launched a major investigation, and we tracked these guys down,” says Clancy. “They weren’t trying to build an explosive, they were making synthetic marijuana.” Nevertheless, the case showed Tripwire’s worth. “We thought that was a real success because people knew, ‘I better call the JTTF on this one,’” he says.
The program is resource intensive, because tips require agent follow-up. Clancy, however, could not divulge how much Tripwire costs because there is no line item for it in the FBI budget.