If you are applying for citizenship or other immigration services from the US Government, then the answer may be yes. The Electronic Freedom Foundation (EFF.org) has obtained internal memos from the Office of Fraud Detection and National Security of the US Citizenship and Immigration Services via the Freedom of Information Act that describe methods employees might use to spy on applicants via social networks.
Some of the advice seems pretty dated, such as assuming those with large friend networks are “narcissistic” and likely to friend people they don’t really know. The EFF suggests that the internal instructions for employees of the US Immigration is to “friend” applicants or possibly even disguise your government affiliation to get access. Then, when the applicants are posting their activities, the employees can discern whether there is evidence of falsified relationships or fraudulent activities.
It’s probably not the best use of government funds to give employees free access to Facebook from work so they can “snoop” on applicants. It’s more likely that the workers would get distracted by their own social network and waste valuable work hours posting photos, tagging their friends and playing Farmville. Even if you had been someone who’d friended Russian spy Anna Chapman on Facebook, there isn’t evidence that her posts there would have revealed her anti-American activities. Of course, now that she’s been returned to Russia, her social networking activities have blossomed. She even has a Facebook poker app that gives the subscription holder access to her actual Facebook posts.