Civil Liberties

E-ZPass readers are used for more than collecting tolls in New York.

Law enforcement agencies know a lot about the whereabouts and daily habits of millions of American motorists through the use of automated license-plate readers. Motorists, on the other hand, don't know much about the records police officers have collected through the use of these machines. These records are getting harder to obtain.

Law enforcement officers across the country have been using a private intelligence network to compile and share detailed information about motorists in the United States.

Police officers in Fort Worth, Texas, set up a roadblock on a busy city street last week, and directed motorists into a parking lot, where they were asked to submit samples of their breath, saliva and blood.