In which landmark ruling did the Supreme Court examine the psychological impact of prison environments and hold that prolonged 'Solitary Confinement' of a prisoner is substantive cruelty that violates the right to life under Article 21?

Explanation

In Sunil Batra vs. Delhi Administration (1978), the Supreme Court directly checked prison conditions. The court held that solitary confinement or keeping a death-row convict apart from other prisoners for extended periods without specific judicial backing strips them of basic human dignity, violating Article 21. It established that even convicts retain their fundamental rights behind bars, subject only to lawful custodial limitations.