sentences:  The Garda National Bureau of Criminal Investigation consists mainly of detectives, who are generally senior investigators, and is headed by an officer of Detective Chief Superintendent rank.The head of the Garda NBCI reports to the Assistant Commissioner in charge of Special Crime Operations, who reports directly to the Garda Commissioner.The NBCI was established on January 21, 1997, centralising other investigative branches around the country, as a response to the proliferation of serious and organised crime.