By social media editor Melony Roy

PHILADELPHIA (CBS) — Did Facebook break any laws by controlling user news feeds for a university study on manipulating emotions? The social network’s “terms of service” policy permitted it, but that policy was updated four months after the study.

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Facebook manipulated the News Feeds of more than 600 thousand people to see if showing them mostly positive or negative posts affected their emotions (read related story).

Drexel cyber security expert Rob D’Ovidio says the study was unethical, but not illegal.

“I do think they covered themselves in this end user agreement,” he says.

Facebook’s Data Use Policy was changed four months after the research and now includes the warning that user information might be used for “internal operations” including “research.”

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“The average person is not going to understand that this covers Facebook using the data its collected for the purpose of manipulating emotion,” Rob D’Ovidio says. “People did not sign on for this.”

There was also no age filter set so the study may have included users under the age of 18 without their parents’ consent.

“I think the threshold for whether this was acceptable or not rises above whether this was legal,” says Rob D’Ovidio, “and if Facebook is going to hide behind the fact they didn’t do anything illegal, users should run and run quickly.”

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