Step 1: Understanding the Concept:
The relationship between Fundamental Rights (FRs - Part III) and Directive Principles of State Policy (DPSPs - Part IV) has been a subject of constitutional debate. While FRs are justiciable (enforceable by courts), DPSPs are non-justiciable. The question is about which landmark case established the harmony and balance between these two parts as a 'basic structure' of the Constitution.
Step 2: Detailed Explanation:
- Background: The 42nd Constitutional Amendment Act, 1976, had inserted clauses into Article 31C that gave primacy to all DPSPs over the Fundamental Rights guaranteed under Articles 14, 19, and 31. This amendment effectively sought to make DPSPs superior to some of the most crucial FRs.
- Minerva Mills v. Union of India (1980): The Supreme Court, in this case, struck down these provisions of the 42nd Amendment. The Court held that the Indian Constitution is founded on the bedrock of the balance between Part III (Fundamental Rights) and Part IV (Directive Principles). To give absolute primacy to one over the other would be to disturb the harmony of the Constitution. The Court famously stated that FRs and DPSPs are "like two wheels of a chariot" and that the harmony and balance between them is an essential feature of the basic structure of the Constitution.
- Other Cases:
- Kesavananda Bharati v. State of Kerala (1973): This case established the 'basic structure' doctrine itself, but the specific application to the balance between FRs and DPSPs was cemented in Minerva Mills.
- Indira Nehru Gandhi v. Rajnarain (1975): This case applied the basic structure doctrine to strike down the 39th Amendment, which had placed the election of the Prime Minister beyond judicial review.
- Kihoto Hollohan v. Zachillhu (1992): This case dealt with the constitutionality of the anti-defection law (Tenth Schedule).
Step 3: Final Answer:
The Supreme Court explicitly held that the balance between Fundamental Rights and Directive Principles is part of the basic structure of the Constitution in the Minerva Mills v. Union of India case.