It hinges on the following bargain: An immigrant who ignored a deportation order and doesn't have a criminal record walks into an ICE office and agrees to be deported. In return, ICE agents won't arrest him or his family on the spot or in the dead of night and will give them up to three months to arrange their departure.

Now, a national crackdown on illegal immigration threatens their shadowy status, and a weak economy makes staying less attractive.About 457,000 scofflaws are eligible under the new ICE experiment. "It gives them an opportunity to take control of their situation. We will give them ample time to get their affairs in order and them go out on their own terms," ICE Assistant Field Office Director Eduardo Preciado said.

It's an offer many will surely refuse. MORE