"Last Spring, wireless carriers and the government jointly announced that they'd be collaborating on building a new nationwide database to track stolen phones (specifically the IMEI number*). The goal was to reduce the time that stolen phones remain useful, thereby drying up the market for stolen phones and reducing the ability of criminals to use the devices to dodge surveillance.
To which critics say:
The thing about kill switches is that they're a manifestation of digital rights management. In the hands of individuals, perhaps they're a good idea. But they won't remain in the hands of individuals. They will be used by companies, organizations, and governments, too. And even when people believe they have control of their kill switches, authorities and hackers can be expected to prove otherwise."
UPDATE: Mikulski Says Cellphone ‘Kill Switch’ Fears Baseless, ‘Conspiratorial’
* You can display your IMEI number by dialing *#06# on your cell phone. [clipper]