"An employee with access to the Secret Service's Twitter account, who mistakenly believed they were on their personal account, posted an unapproved and inappropriate tweet," read a statement from the U.S. Secret Service. "We apologize for this mistake, and the user no longer has access to our official account. Policies and practices which would have prevented this were not followed and will be reinforced for all account users."
The tweet was made via iPad, so I’m guessing a GLBT liaison working in the WH got hold of the official Secret Service Twitter account.
Over two years in and it's still Amateur Hour at the WH.