Tamerlan Tsarnaev, the primary conspirator in the Boston Marathon bombing that killed three people, slipped through airport security because his name was misspelled in a database, according to a new Congressional report. As a result, Tsarnaev was entered into two US government databases: the Terrorist Identities Datamart Environment and the Treasury Enforcement Communications System (TECS), an interagency border inspection database. A special note was added to TECS in October of 2011, according to NBC News, requiring a mandatory search and detention of Tsarnaev if he left the country.