In the case of Minerva Mills v. Union of India (1980), the Supreme Court of India held that the attempt to accord primacy to the directives over fundamental rights was unconstitutional.

The case involved a constitutional challenge to certain provisions of the 42nd Amendment Act, 1976, which had made significant changes to the Constitution of India. One of the key changes made by the amendment was the insertion of Article 31C, which sought to give primacy to the Directive Principles of State Policy over fundamental rights.

The Court, in a majority decision, struck down Article 31C as unconstitutional and upheld the primacy of fundamental rights. The following are the key reasons for the Court's decision:

1. Violation of the Basic Structure Doctrine:
The Court held that Article 31C violated the basic structure doctrine, which states that certain fundamental features of the Constitution cannot be amended. The Court reasoned that giving primacy to the directives over fundamental rights would undermine the balance and harmony between the two and upset the basic structure of the Constitution.

2. Restriction on Judicial Review:
Article 31C sought to restrict the power of judicial review by providing that laws made to implement the Directive Principles would not be invalidated on the ground of violation of fundamental rights. The Court held that such a restriction on judicial review was arbitrary and against the principles of separation of powers.

3. Equality before the Law:
The Court also noted that Article 31C violated the principle of equality before the law enshrined in Article 14 of the Constitution. By according primacy to the directives, the amendment would have allowed the State to discriminate against certain individuals or groups in the name of implementing social and economic policies.

4. Harmonious Construction:
Lastly, the Court emphasized the need for a harmonious construction of the Constitution, where fundamental rights and Directive Principles are read together. It held that both are complementary to each other and should be interpreted in a manner that upholds and promotes the welfare of the people.

In conclusion, the Minerva Mills case foiled the attempt to accord primacy to the directives over fundamental rights by striking down Article 31C of the Constitution. The Court upheld the importance of fundamental rights and the need for a harmonious balance between fundamental rights and Directive Principles.