Gov. Chris Christie isn't the only person who can use metadata against a politician.

The Associated Press reported Tuesday that Rep. Aaron Schock (R-Il.) has "spent taxpayer and campaign funds on flights aboard private planes owned by some of his key donors." It discovered this, in part, because of data from Schock's Instagram.

Schock is said to have taken more than $40,000 worth of flights on donors' planes since mid-2011. He is already facing an ethics inquiry for allegedly soliciting funds in 2012. Here's how the Associated Press discovered this additional ethics breach:

The AP tracked Schock's reliance on the aircraft partly through the congressman's penchant for uploading pictures and videos of himself to his Instagram account. The AP extracted location data associated with each image then correlated it with flight records showing airport stopovers and expenses later billed for air travel against Schock's office and campaign records.

The Associated Press didn't need to analyze the content of the images to learn about Schock's travels. (Though the images did apparently include selfies at concerts and other events paid for with taxpayer money.) All it needed was the location metadata.

Christie used similar information for a more nefarious purpose when he fought with Sen. Frank Lautenberg (D-NJ) over fare hikes on bridges and tunnels to New York City. As the American Civil Liberties Union explained in a post on Christie's actions:

[T]his incident ties together a lot of the reasons we worry about privacy: that location data is very personal (as we tried to convey last year in this video). That information is power and always raises the temptation for abuse through Nixonian dirty tricks, embarrassment of rivals, or leverage over critics. And that every incident of abuse that actually happens casts a long shadow of chilling effects over those who just worry about how data might be used. If officials feel comfortable using information against a senator, what is a lower ranking political official, let alone ordinary citizen, supposed to conclude about how data could be used against them?

This reporting lends more support to the notion that metadata isn't personal -- as if that idea should even be contested at this point -- and shows that governments and businesses aren't the only ones that can use metadata to learn more about people.

And unlike those other groups, the Associated Press simply used location metadata from an Instagram feed anyone could view and cross-referenced it with information to which the public has a right to access. There was nothing shady about its methods.

Maybe politicians will take concerns about gathering metadata a little more seriously now that they know their every digital move can be used to hold them accountable to the public. Or perhaps they'll just take their Instagram accounts private. Either one.

[image public domain]