Facebook’s recent psychological experiment on 700,000 unwitting users should spur the Federal Trade Commission to examine the ethical issues raised by online research, two professors say in a letter to the agency. “The Federal Trade Commission is uniquely positioned to safeguard consumers when they are subjected to experimental research by Facebook and other companies,” University of Maryland law professors James Grimmelmann and Leslie Meltzer Henry wrote today to the FTC. “The FTC has already studied the information that companies collect on consumers retrospectively and taken action to prevent misuse of that information,” they add, referring to the agency's recent report on data brokers. “Here, it can protect consumers prospectively, by ensuring that they give genuinely informed consent when they take part in human subjects research.” The law professors are reacting to the news that Facebook tinkered with news feeds of nearly 700,000 people in order to test whether their moods would be influenced by friends' posts. For the study,published last month in the prestigious Procecedings of the National Academy of Sciences, Facebook manipulated users' news feeds to deliberately filter out some positive or negative posts. Researchers then made note of users' reactions and concluded that mood was “contagious,” with users' responses matching the tone of the posts they saw. That is, people shown more negative posts themselves began posting more negative material, while those shown more positive comments themselves posted in a more positive tone. Grimmelmann and Henry say in their letter to the FTC that Facebook never obtained users' “informed consent,” which generally requires researchers to tell people they will be used as subjects in a study, outline the risks and benefits, and then get their explicit permission. The law professors also point out that Facebook's data use policy doesn't in any way put people on notice that they might be used as subjects in a psychological experiment. “Taking action here will advance the FTC’s core mission of preventing 'unfair or deceptive acts or practices' harming consumers,” Grimmelmann and Henry write. They add that subjecting people to secret experiments can be a deceptive trade practice: “The failure to disclose research is an omission that a reasonable consumer would consider material in deciding whether or not to use a service,” the law professors write. Grimmelmann and Henry are now calling for new FTC-imposed safeguards -- including a requirement that Facebook get “genuinely informed consent” from people before using them in experiments. Grimmelmann also want the FTC to investigate any other studies Facebook has conducted, what risks they posed and whether the company attempts to exclude minors from the pool of subjects, among other issues. The law professors aren't the only ones asking the FTC to get involved. In recent weeks, the watchdog Electronic Privacy Information Center filed a complaint with the FTC about Facebook's experiment, and Sen. Mark Warner (D-Va.) asked the agency to investigate the potential ramifications of the social networking service's research on its users.