On Tuesday, 18 Nov 2014, Twitter announced that it has finished indexing every public tweet ever made since the social networking service launched in 2006.
Fortunately for investigators, Twitter does not provide bulk deletion. This means that most people will not take the time to examine their Tweets for Bozo Eruptions. However, batch deletions are possible, by using third-party sites like Tweet Deleter, Tweet Eraser and TwitWipe. If someone deletes some Tweets, Twitter admits that “Deleted tweets sometimes hang out in Twitter search, [but] they will clear with time.” Unfortunately, when a user deletes a tweet, it eventually disappears from Twitter’s search results, as well as from any accounts that follow the account along with any retweets of the deleted tweet.
Fear not intrepid investigator, fore hope and a lot of searching might uncover someone who copied into his own tweet a deleted tweet, which will remain as will any tweets quoted on sites elsewhere.