A deputy commissioner is a police, income tax or administrative official in many countries.
Deputy Commissioner of Taxes (popularly abbreviated as DCT) is an Income-tax authority.
Deputy Commissioner of Taxes are basically officers of BCS Taxation Cadre.
A district magistrate is also authorised to collect Land Revenue and is therefore also referred as a collector (revenue) and also to control encroachment of government land in the district.
The rank insignia is a sword and a rectangular cylinder crossed over each other with a single star above.