Last week, the government unsealed a plea agreement in a terrorism case involving Najibullah Zazi, the Denver shuttle bus driver the FBI arrested last September. He allegedly conspired to target New York City subways at the direction of al-Qaida. Attorney General Eric Holder has said that Zazi's plot was the most dangerous on American soil since Sept. 11. He's pleaded guilty to terrorism charges.
Though he pleaded guilty, Zazi still faces life in prison. The question has been: Why would he agree to that?
It turns out Zazi is cooperating with prosecutors -- which might win him and his family a so-called "snitch" visa.
The 'Snitch' Visa
The visa is a little-known bargaining chip that the government can dangle before terrorism suspects who agree to cooperate with investigators and plead guilty. It can sweeten the idea of decades behind bars.
"We always refer to the S visa as a snitch visa," says Patrick Rowan, who ran the national security division at the Justice Department during the Bush years. "It was always easy to remember because you would use the word snitch."
Rowan says the idea behind the visa program is simple.
"The essence of the S visa is there's people who are in the U.S. who you would want their cooperation in the context of a criminal case," Rowan says. "And you can gain them status in the U.S. so they can live here and work here and even have a path toward becoming a lawful permanent resident if they're granted an S visa."
So that's what the government can offer. Zazi's case helps explain what it might get in return.