K.M. MOHAMAD ABDUL KHADER FIRM vs STATE OF TAMIL NADU & ORS.

The Supreme Court upheld the constitutional validity of the Tamil Nadu Additional Sales Tax Act, 1976, ruling that the amended Section 2 does not lack legislative competence and does not impose a tax on income but rather modifies the method of computing the Additional Tax. The Court found no violation of Articles 14, 19, or 301 of the Constitution, affirming that the changes in the mode of levy do not alter the nature of the tax. The petitioners' challenges to the assessment orders were dismissed, confirming the legality of the graded rates imposed under the Act.