The DCI is a nodal agency of Income Tax Department for strengthening tax data- base. Its key function areas are (i) widening of tax base through identification of stop filers and non-filers (ii) Deepening of tax base by providing information for proper selection of cases for scrutiny assessments (iii) through collection, collation of information from internal as well as external sources and its dissemination to Assessing officers (AOs) and other users in I.T.Deptt. It also collects information relating to financial transactions like investment, expenses, payment of taxes, etc and details of persons who are involved in some specified activities. The mandate also provides for identification and investigation of cases of tax evasion arising out of criminal matters, having any financial implication punishable as an offence under any Direct Tax Law.