With the prevalent use of social media, litigants need to be mindful of how social media can affect the outcome of a case. In Gatto v. United Air Lines, Frank Gatto sued United Air Lines and Allied Aviation Services for injuries he sustained on the job from an accident at John F. Kennedy Airport. United Airlines and Allied requested that Gatto turn over any documents or information related to his social media accounts. Gatto’s actions ended up hurting his case.

Even though under court order to provide access to his Facebook account, Gatto deleted the account, saying that he thought it had been hacked. The court said that because Gatto intentionally deactivated his Facebook account, it would instruct the jury at trial that it could assume that when Gatto deactivated his Facebook account, he was intentionally destroying damaging evidence.
The lesson here is that photographs and posts on social media can be relevant evidence in a lawsuit and may provide information that cannot be found elsewhere. If a proper discovery request is made, the owner of the social media may be obligated under the law to preserve any information in the accounts, just like any other type of documentation or information requested. 
For more, read this blog discussing the applicability of the Federal Stored Communications Act to Facebook posts and this related case.