Anti-Corruption branch of the State headed by a Dy. S.P. level officer came into existence in the year 1946 under overall control and supervision of D.I.G, CID, Assam.One post of S.P. Anti-Corruption branch was created in the year 1959 vide Letter No.HPL.321/57/46 Dated 04-04-1959. Consequent upon the recommendations of the “Santhanam Committee” a post of Vigilance Commissioner was created by the State Government in 1964 vide no.PLA.473/64 dated 30-09-1964.
During this period, the Anti-Corruption branch, which used to be under control of the Dy. I.G., CID was placed under the Vigilance Commissioner. The post of the State Vigilance Commissioner was held by retired Judges of the High Court till 1981.ACB was declared as Police Station in the year 1975. A Separate Directorate of Vigilance & Anti-Corruption was established in 1983 which was headed by an I.G.P. Rank officer.Vide Government Notification Dated 28-06-1991, Officers under the Director General of Vigilance & Anti-Corruption, Assam, not below the rank of Inspector of Police were authorized to investigate an offence punishable under the Prevention of Corruption, Act, 1988.