It looks like the folks in and around DC want to tag along in a big way on the license plate reader idea:
Security officials to scan D.C. area license plates
Security officials to scan D.C. area license plates
August 18, 2008 - 10:24am
WASHINGTON (AP) - Homeland security officials in the Washington area plan to dramatically expand the use of automated license plate readers to prevent possible terrorist attacks.
Officials from Maryland, Virginia and the District of Columbia have agreed to install 200 license plate readers on police vehicles, at airports and along roads. The plan announced Friday will be funded by federal homeland security grants for the area.
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The readers will scan every license plate that passes by and will run the numbers through federal criminal and terrorist databases.
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New York officials recently said they plan to scan license plates of all cars entering Manhattan.
Privacy experts say it's a vast expansion of the use of technology for security.