Fortune magazine released a six-month investigative report in Operation Fast and Furious. Here's a timeline based on that report and other sources.
—1993-2005: ATF reputation suffers in high-profile cases.
—October 31, 2009: Operation Fast and Furious is launched.
—December 2009: David Voth heads Phoenix Group VII, which lacked funding, to stop guns from going to going to Mexico criminals.
—January 5, 2010: In Phoenix, assistant U.S. Attorney Emory Hurley tells agents they lack probable cause for arrests as multiple long gun purchases are legal in Arizona. He suggests a wiretap. Voth later writes a briefing paper stating strategy "to allow the transfer of firearms"—because that is legal.
—January 18, 2010: James Avila, a drug user and transient, purchases three WASR-10 rifles. ATF is notified over the Martin Luther King Jr. weekend, so agents lose the chance to seize them, but input the serial numbers in the gun database. These are the guns that are found at the Brian Terry shootout.