Guarding Our Privacy

A few years ago, Scott McNealy, the CEO of Sun Microsystems, quipped, “Privacy is dead. Get over it.”

Latanya Sweeney doesn’t like that. You can see it in her body language as she leans forward on her chair. “Privacy is definitely not dead.” And those who believe it is “haven’t actually thought the problem through, or they aren’t willing to accept the solution.”

But even if our privacy hasn’t yet evaporated, Sweeney admits it’s in increasingly short supply. The post 9/11world has left us rattled, and inclined to trade personal rights for larger helpings of national security. And digital technologies make our lives downright porous. Bits and pieces slip into the Internet; our identities are scattered throughout endless databases; conversations dangle out there on cell phones, and revealing email flits from here to there on wireless networks. Balancing the safety of many against the primal need to keep at least a few secrets personal is one of the big, jagged issues of the 21^st century, and some can’t see a way to clamp a lid on it.

Given her concerns you might mark Sweeney as a political activist or crusading journalist. And if you happen to see her cruising the highways and hills of Pittsburgh, decked out in leather, on her Honda VTX 1300 motorcycle, who could blame you. But she isn’t. Instead she’s deadly good with numbers, and she likes to shape them into formulas and algorithms that let us all keep a little information about ourselves to ourselves. Anyway, that’s the job she created when she founded the Laboratory for International Data Privacy at Carnegie Mellon University. The work, she says, gets more interesting every day.

Sweeney has been inclined to mathematics since her childhood growing up in Nashville, Tennessee where her grandparents raised her. In those days she used to imagine creating an artificially intelligent machine that she could talk with and learn from. “I guess I would get bored in class, “ she says matter-of factly. “ I spent hours fantasizing about that box.”

She came to Carnegie Mellon on the back of her fascination with numbers and her concern for privacy, but it was a zigzag route. First Wellesley, then a suite of scholarships brought her to MIT, seemingly the perfect fit for her talents. But MIT’s male-dominated geek culture was a tough transition. When one day a professor suggested the class use a peculiar mnemonic to recall the "resistor code" -- the color bands that mark electrical resistors in a circuit, she decided MIT wasn’t for her. The phrase went like this: "Black boys rape only young girls but Violet gives willingly."

A Software Solution
Sweeney soon founded a software-consulting firm where she worked for the next ten years helping clients keep their digital systems tweaked and humming. Privacy wasn’t yet on her radar. That came when she returned to academics, completed her undergraduate degree at the Harvard Extension School and then headed back to MIT to earn her masters and doctorate in computer science. While at MIT she wanted to return a favor for a fellowship she had received from the National Library of Medicine, and found herself working with Boston area hospitals to improve the privacy of their patient records. Confidential medical information was seeping into the still embryonic, but very public, World Wide Web, and the hospitals wanted to put a stop to it.

Sweeney developed new software she called “Scrub System” that was able to march through thousands of medical records, find so-called “explicit identifiers” – names, addresses, social security numbers -- far better than standard “find and replace” programs, and then scrub them out so that they couldn’t be plucked off the Internet by someone else.

Hospital records are particularly sensitive because knowing all about your health, or mine, health can be bent in especially appalling ways. An insurance company might use it to deny coverage to someone who has a preexisting condition; potential employers might use the information to pass over a problematic job applicant. Sweeney’s research even turned up a loan officer at a Maryland bank who cross-referenced his customer records with publicly available databases on cancer patients. When he found any loan-holders who had cancer, he called in their debts.

Bringing it to Pittsburgh
Scrub System won several awards, which eventually led to multiple job offers including ones from Stanford and Carnegie Mellon. She took the Carnegie Mellon offer, she says, because “I felt as though there was a neon light telling me to come here...When I saw how easy it would be to work across disciplines, and the advantage that gave me in deploying a new kind of computer science, I was hooked… And I fell in love with Pittsburgh. The quality of life is head and shoulders above larger cities like New York, Boston and San Francisco,” because it offers so many first class amenities without any of the big city hassles.

But even with her new lab in place, Sweeney found preserving privacy tougher than she had originally suspected. In the 90s she thought her award winning software had solved the “privacy problem.” But today, she admits, “I really didn’t understand a thing about it.”

She first had that insight one day when she was still at MIT. She had been reading the medical history of a young woman. “At age two this girl was sexually molested, at age three she stabbed her sister with scissors, at four her parents got divorced, at five she set fire to her home,” says Sweeney. Nothing in the report specifically identified the girl, but her experience was unique, and Sweeney was pretty sure she could use it to figure out who she was. Obviously, removing “the explicit identifiers wasn’t what [privacy preservation] was about.” It was about tracking the shreds of personal information we leave innocently behind in records strewn all over the Internet— on medical forms, credit applications, resumes and surveys.

That, in effect, is what the Data Privacy Lab does. She and her team of graduate students often play the role of cyber-world bad guys, devising smart algorithms that unveil chinks in databases, the World Wide Web, video surveillance systems, whatever the job calls for. In one experiment, the team cut a program called Identity Angel loose on a slice of the Internet. It quickly located and cross-referenced enough names, addresses, dates of birth and social security numbers to snatch up 10,000 identities. The lab didn’t steal them, of course, instead it notified everyone that they were at risk, but the point was made: If we can do it, so can plenty of others. “Research by fire,” Sweeney calls it.

Despite her lab’s work, and after advising government agencies, hospitals and corporations around the country about preserving privacy, Sweeney says the ultimate solution isn’t to keep sticking our fingers in the cyber-dike. “We’ll never keep pace,” she says. Instead engineers and computer scientists have to start building privacy protection into the technologies they create before they hit the market. They will be more commercially successful if they do, she argues.

And so, in between jaunts on her VTX 1300, that’s what she and her lab concentrate on now. Training a new generation of engineers and computer scientists. They have a pretty good partner too – Intel, the world’s largest computer chip manufacturer. Privacy may make a comeback yet.

For more about Latanya Sweeney’s work and lab visit: http://privacy.cs.cmu.edu/. To read a profile and an interview with her in Scientific American magazine click here and here. 

Chip Walter’s latest book is Thumbs, Toes and Tears – And Other Traits That Make Us Human, available at Amazon.com or a major bookstore near you. He is now at work on his next book entitled (for now) Anatomy of Desire – Why We Think, Feel and Do the Crazy Things We Do. He can be reached at six.traits@gmail.com.