Harvey said investigators look for any "derogatory" behavior that could damage the agency's reputation.
E. Chandlee Bryan, a career coach and co-author of the book "The Twitter Job Search Guide," said job seekers should always be aware of what's on their social media sites and assume someone is going to look at it.
Bryan said she is troubled by companies asking for logins, but she feels it's not a violation if an employer asks to see a Facebook profile through a friend request. And she's not troubled by non-disparagement agreements.
"I think that when you work for a company, they are essentially supporting you in exchange for your work. I think if you're dissatisfied, you should go to them and not on a social media site," she said.
More companies are also using third-party applications to scour Facebook profiles, Bryan said. One app called BeKnown can sometimes access personal profiles, short of wall messages, if a job seeker allows it.
Sears is one of the companies using apps. An applicant has the option of logging into the Sears job site through Facebook by allowing a third-party application to draw information from the profile, such as friend lists.
Sears Holdings Inc. spokeswoman Kim Freely said using a Facebook profile to apply allows Sears to be updated on the applicant's work history.
The company assumes "that people keep their social profiles updated to the minute, which allows us to consider them for other jobs in the future or for ones that they may not realize are available currently," she said.
Facebook declined to comment except for issuing a brief statement declaring that the site forbids "anyone from soliciting the login information or accessing an account belonging to someone else."
Giving out Facebook login information also violates the social network's terms of service. But those terms have questionable legal weight, and experts say the legality of asking for such information remains murky.
The Department of Justice regards it as a federal crime to enter a social networking site in violation of the terms of service, but during recent congressional testimony, the agency said such violations would not be prosecuted.
Lori Andrews, a law professor at IIT Chicago-Kent College of Law specializing in Internet privacy, is concerned about the pressure placed on applicants, even if they voluntarily provide access to social sites.
"Volunteering is coercion if you need a job," Andrews said.
Twitter did not respond to repeated requests for comment.
In New York, Bassett considered himself lucky that he was able to turn down the consulting gig at a lobbying firm.
"I think asking for account login credentials is regressive," he said. "If you need to put food on the table for your three kids, you can't afford to stand up for your belief."
McFarland reported from Springfield, Ill.
Manuel Valdes can be reached at https://twitter.com/ByManuelValdes .
Shannon McFarland can be reached at https://twitter.com/shanmcf .
Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.