This is bad for privacy, showing how police can track anyone's movements through a private camera network without a warrant or court oversight.

• Flock runs a nationwide network of license-plate and street cameras that cities install at intersections.
• Local police pay a monthly subscription and log into a cloud dashboard to search the footage.
• Officers can pull up anyone's timeline and trace everywhere a person has been — no warrant needed.
• They can download stills or full video and feed it into outside facial-recognition tools to identify people.
• The warning: without new rules, this quietly builds a mass-surveillance system like London's or China's.

Outlook: Expect growing pressure for laws to limit warrantless police access to these camera networks as their reach becomes clearer.