The man who hacked Selena Gomez's Facebook page has been jailed for a year.Fast food worker Gareth Crosskey gained access to the Disney star's profile in January 2011 by posing as Gomez's stepfather Brian Teefey, who administrates the page, and persuading Facebook bosses to reset her password.Crosskey is alleged to have threatened Teefey with releasing several personal messages between Gomez and Bieber, who at the time had not confirmed their relationship.He was tracked down after a £50,000 joint investigation between the Metropolitan Police's e-crime unit and the FBI.