I suppose "people" are a little sensitive right now to warrantless searches by government law enforcement people. We're in the midst of the snoopgate scandal, in which the Bush administration has admitted to spying on Americans. And, in which, the Echelon system has been implicated in being used in snoopgate by the NSA to vacuum up all communications for analysis by the NSA.
It's in this context we learn: Officials: Muslim sites subject to secret monitoring for radiation (From Kevin Bohn and Jeanne Meserve, CNN, Saturday, December 24, 2005)
This is about the FBI and/or other agencies monitoring radiation levels at specific places inside the U.S. A major target are mosques and other muslim-connected places. While the article says some non-muslim sites were also monitored, the article shows outrage from muslim spokespersons basically complaining of racial targeting.
One thing the article discusses is the warrantless nature of this monitoring. Technically a warrant isn't required because radiation can be monitored from a distance. And, for that matter, other government agencies do warrantless monitoring like this all the time. For example the FCC regularly monitors for illegal radio stations, simply by listening on the radio and using radio direction finder equipment to narrow down the broadcast location.
The program is part of the "dirty bomb" meme that's been running around for a long time. You know this one ... in the confusion shortly after September 11, 2001, someone was accused of a dirty bomb plot. A dirty bomb is a regular chemical explosive device that's been laced with radioactive material. The idea is to spread the radioactive material over a large area through the explosion. But ever since that accusation one of the scares which are repeatedly reinforced in the public mind is this dirty bomb meme.
One possibility I see here is to make monitoring equipment ubiquitous. Rather than this being a special arrangement, suppose all the street lights had equipment mounted on them to monitor air pollution, temperature, rain, radiation, various chemicals, etc. The equipment would need to transmit the data "home" to a data collection repository. That would provide a very interesting set of data not just for law enforcement, but also environmental monitoring and climatology.
Already there are a slew of video cameras being installed by governments. Why not add to them other kinds of monitoring?