THE AMALGAMATED COALFIELDS LTD. AND ANOTHER vs THE JANAPADA SABHA, CHHINDWARA (And connected appeals)

The Supreme Court upheld the validity of the coal tax imposed by the Independent Mining Board, rejecting the appellant's challenge based on res judicata under Articles 32 and 226 of the Constitution. The Court clarified that while res judicata applies to writ petitions, it does not impair the assertion of fundamental rights. The Court also ruled that the assessment procedure for tax was not arbitrary and did not violate Article 19(1)(f). The writ petition was dismissed, affirming the High Court's decision that the matter was concluded by the earlier judgment.