The Supreme Court of India recently decriminalised homosexuality by passing a landmark judgment in the case of Navtej Johar and Others v. Union of India. In its judgment, the Court held that Section 377 of the Indian Penal Code, 1860 is unconstitutional in as much as it criminalises consensual sexual acts between two adults. The Court held that Section 377 discriminates against persons of the LGBTIQ community based on their sexual orientation and violates their fundamental rights guaranteed by the Constitution of India. The Court arrived at this conclusion after considering established principles of constitutional law, foreign precedents and expert opinions. However, a crucial part of the Court’s reasoning was based on a close reading of the Mental Healthcare Act, 2017. The Court relied on the anti-discriminatory provisions of the Mental Healthcare Act, 2017 to observe that homosexuality is not a mental illness or mental disorder, and that LGBTIQ persons cannot be discriminated against on the basis of their sexual orientation. The Court’s reading of the Mental Healthcare Act, 2017 and Section 377 is significant as its rationale can be extended further to challenge other laws which discriminate against persons with mental illness. The Court also highlights the responsibilities of mental health professionals and counsellors while providing mental healthcare to LGBTIQ persons. Finally, the Court’s reading of the Mental Healthcare Act, 2017 is also a recognition of its commitment as an anti-discrimination legislation which upholds constitutional values and protects the rights of persons with mental illness.