When you ask Siri late on a Friday night how to craft the perfect booty text, it’s not like the iPhone’s digital assistant is going to run off and tell your friends. But oh, she remembers what you tell her. As for how long she holds onto that info, well, it’s unclear. And that uncertainty over Apple’s data retention police is giving privacy advocates a severe case of the frownfaces.

In all seriousness, it’s important to know what information companies like Apple are collecting, and how long they’re holding onto it. The European Union made Google, Yahoo and Microsoft cough up precise information on what they do with search data, notes Wired.com’s Robert McMillan, but Apple isn’t saying how long Siri remembers all those personal things you tell her.

In the Siri Privacy agreement (which is incredibly difficult to find, natch, but is located in the phone’s settings if you’re going to turn switch Siri off), Apple says it deletes user data as well as “recent” searches with Siri every time you turn her off. What about all the things you murmured to her a year or so ago? That’s up in the air.

“If you turn off Siri, Apple will delete your User Data, as well as your recent voice input data,” Apple’s privacy statement reads. “Older voice input data that has been disassociated from you may be retained for a period of time to generally improve Siri and other Apple products and services.”

It could be weeks or months, or it could be years, and that has the American Civil Liberties Union worried.

“It’s not clear what ‘disassociated’ means. It’s not clear what ‘period of time’ means. It’s not clear what using it to ‘generally improve Siri and other Apple products and services’ means,” Nicole Ozer, a lawyer with the ACLU told Wired.com. “The only thing that’s clear is we really don’t know what may be happening to the personal information we have told Siri, even after we turn Siri off.”

Big deal, so what, who cares if you ordered four pizzas to eat alone at 1 a.m.? It matters because if that’s stored on Apple’s servers, marketers could use it to sell you things or worse, that info could be subpoenaed in a civil suit down the line.

“People say very personal information to Siri,” Ozer says. “They are encouraged to think of Siri as their confidante and their assistant. But Siri is not just working for you. Siri is collecting a lot of data for Apple and for its business. And people should be very mindful and aware of what’s happening to their personal information; how it’s being used; and be able to make informed decision about whether or not they want to be sharing certain information with Siri.”

While Siri can surely be useful, you might want to think carefully about what you tell her — at least until Apple comes clean about its data retention policies, which it has yet to do.

Siri Remembers Your Secrets, But for How Long? [Wired.com]

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