Demonstrators with Guy Fawkes masks protest changing privacy policies on March 31, in Vienna. Ronald Zak/DAPD/AP hide caption

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In politics, video tracking has become normal. And it's a growth industry. There are trackers working for campaigns, political parties and, increasingly, political action committees. iStockphoto hide caption

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The Seattle Space Needle's 50th anniversary is Saturday. Though the top of the Needle has been off-white for years, it's being painted its original color, "galaxy gold," for the anniversary. Dan Callister/Getty Images hide caption

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Several Web browsers, including Mozilla's Firefox, enable users to request additional privacy online via a "do not track" button. But there's no consensus on how much privacy the button should offer users. Leon Neal/AFP/Getty Images hide caption

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Protesters demonstrate at City Hall in Seattle on Feb. 16, 2011, after the announcement that police officer Ian Birk would not face charges for the fatal shooting of John T. Williams. Ted S. Warren/AP hide caption

itoggle caption Ted S. Warren/AP

Then-Capt. Brent Clemmer said Staff Sgt. Robert Bales distinguished himself as a team leader in Clemmer's C Company, 2nd Battalion, 3rd Infantry Regiment during the Battle of Zarqa, Iraq. The faces of the rest of Bales' squad have been obscured. Courtesy Maj. Brent Clemmer hide caption

itoggle caption Courtesy Maj. Brent Clemmer

A Washington State Patrol crime lab technician opens DNA sample cards containing cheek swabs sent from jails and prisons. If the state Legislature approves pre-conviction DNA sampling, the number of cards the lab processes could double. Martin Kaste/NPR hide caption

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