The system will allow the NYPD, and possibly the federal government, to create a computerized database on the movement and whereabouts of millions of everyday New Yorkers who travel south of Canal Street.

Modeled after London's so-called Ring of Steel surveillance network, the Lower Manhattan Security Initiative will create a system of thousands of surveillance cameras that will monitor and track vehicles and pedestrians in the financial district. There will be roadblocks, mobile teams of heavily armed officers as well as technology including closed-circuit television cameras, license plate readers and explosive trace detection systems.

In a segment of the plan called Operation Sentinel, the department also proposes to photograph every vehicle entering Manhattan, scan the license plates and use sensors to check for radiation, and then keep the information on file for at least a month.

That's basically all we know. Back in October 2007, the NYCLU filed a Freedom of Information Act request with homeland security, requesting what seems like basic details about the program: the scope of information collected about individuals, how law enforcement folks will use the info and who they will share it with, how long they will store it, which private companies (like banks) will use their own surveillance to participate in the system, and how many taxpayer dollars will go to fund it.

This is the second lawsuit NYCLU has filed about the surveillance program. It sued the NYPD last April in New York State Supreme Court (the lawsuit is ongoing).

At the time, Mayor Bloomberg defended the program in his characteristically blunt way: "We just have to do something here to make the city safer. Sadly, it is a little bit of an infringement on your rights," he told a news conference.