Update: In a second statement to Fusion, Facebook retracted its original statement that location is one of the ways in which it suggests who you may wish to follow, and now says, “We’re not using location data, such as device location and location information you add to your profile, to suggest people you may know. We may show you people based on mutual friends, work and education information, networks you are part of, contacts you’ve imported and other factors.”

Original story:Facebook’s “People You May Know” feature has always been a little hit-or-miss and, frankly, inscrutable. That woman from your high school class, with 29 mutual friends? Yeah, maybe you want to be connected to her. Some guy you never heard of, with one mutual friend, in a city 600 miles away? Not so much. But one of the things Facebook doesn’t usually say about those suggestions is that they may be popping up because those people — or at least their phones — have been in the same room as you at some point.

As Fusion reports, Facebbook’s algorithms for determining which of its 1.6 billion users should show up as “people you may know” are taking location into account… and that may not be a good thing.

Sure, it’s great for networking. Meet someone at a conference, or at a party, and can’t remember their last name? Facebook thinks you may know them, and that’s handy! Now you know that “Jen? Jan, maybe?” who you wanted to follow up with is actually Jane, and you can connect. Convenient.

But it’s really not uncommon to be someplace where you don’t want to make that deep a connection with the other people in the room. A 12-step meeting, for example, is supposed to remain anonymous — participants don’t give surnames or detailed personal information, but Facebook might provide it to other members as a suggestion. Or perhaps the waiting room for a doctor’s office: you don’t want to know everyone else there, and you don’t want all of them to know you, either.

And, like many “convenient” technologies, it opens the door to more danger for folks who are already targeted — women, LGBT individuals, people of color — who may be deliberately trying to avoid contact from hostile harassers who now have their full name and public Facebook information available to them.

On top of all that, of course, there’s the pure fact that location may not be a particularly useful metric at all. Does it mean anything that 7,000 other people were in line for the same ride as you for the same three hours at Disney World in July? Are you badly in need of a digital relationship with your line buddy who happens also to come from the same general metro area as you?

Facebook users who have the app on their phones, either iOS or Android, can disable location features. In the app, under “Account Settings” (not “app settings”), there is a section for “Location,” where you can allow or disallow location access. You can also grant or block location permissions for the app in your phone’s settings.

Of course, with location access disabled, a number of other features Facebook users occasionally enjoy, like the ability to tag into certain venues, or many of the “events” options, will no longer work.

So what’s to do? Well, Facebook could tell people that they’re using location data in this way. Fusion spoke with a law professor at Stanford who told them, “Once Facebook users realize that the ‘People you may know’ are the ‘people who go to the same places you do,’ this feature will inevitably start outing people’s intimate information without their knowledge,” and he’s right.

The professor also said, “This is the kind of thing that people should be given explicit and multiple warnings about … they should also be asked to affirmatively turn on the feature before their whereabouts are used to get them friends.”

Facebook already lets users opt in or out of having their location shared with nearby friends, so letting you opt-out of sharing it with nearby strangers seems only fair.

Facebook is using your phone’s location to suggest new friends—which could be a privacy disaster [Fusion]

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