Online revelations

When Amy Hauch attended law school in Michigan, she wanted to keep in touch with the friends and family she was leaving behind in Pittsburgh.

"When I moved to Michigan, I didn't know anyone," said Hauch, 25, of Jefferson Hills.

So, she signed up with the social networking site Facebook.

"I got on networks, and it helped me meet new people," she said.

But while her personal pictures and information were there for her friends to see, others could look, too.

Privacy settings on social networking sites like Facebook or MySpace will block an annoying co-worker or vindictive ex-girlfriend from viewing a profile, but if there's something illegal there, the filters won't stop police.

"People who join (social networking sites) could be your peers, or they could be the police or future employers," said Alessandro Acquisti, assistant professor of information technology and public policy at the H. John Heinz III School of Public Policy and Management at Carnegie Mellon University.

Hauch said she even reconnected with friends from high school that she hadn't spoken to in years.

All of a sudden, they were back in her life -- they could see pictures of her with her new friends, see where she went on vacation and find out who her friends were.

Acquisti examines why people post and said users should do so with caution.

"It's difficult to forecast the consequences of conveying information," he said, adding that the value of information -- whether good or bad -- can sometimes only be determined after it's too late.

Hauch has privacy filters on her Facebook page, allowing only friends to see the majority of her profile, she said. Still, some information, like what schools she attended and some photos, are open to the public.

Police said the evidence found on the site can be used in a court of law.

"There are backdoors we can access without being a member or having an account," said Detective Chris Jordan of the Pittsburgh computer crimes unit.

If that doesn't work, police can get a search warrant for Facebook, MySpace or any other site, Jordan said.

Earlier this month, Cara Behm, 26, of Williston, Vt., was charged with one count of criminal mischief after someone sent an anonymous tip to the city's 311 hot line when they discovered online photos of her tagging a plaque on Mt. Washington. Defacing public property is an act of vandalism and is illegal.

"(People) don't think they're going to get in trouble for it if their profile is locked down so only friends or family can see," Jordan said.

But if there's something illegal, you'd better know who your friends -- both in cyberspace and in the real world -- are.

Hauch said she doesn't post photos or other incriminating evidence that a future employer might use against her, but has heard of people who have had to take down certain aspects of their profile.

"I heard that depending on what (profession) you're going into, you might have to take stuff down," she said. "But I'm not really concerned."

Both Facebook and MySpace turned down interview requests regarding the matter of privacy rights and public domain for their Web sites, but Acquisti said that while the information's public status depends on the network, the sites should be considered semi-public.

Jordan said people should stop doing illegal things all together, or at least stop posting the evidence.

"People think the computer is nice and safe," he said. "Some people tell their computer things they wouldn't tell their priest or their significant other."