The Supreme Court in Sujit Das v Union of India drew a firm constitutional line between lawful arrest and unlawful detention by holding that any person taken into police custody must be produced before a magistrate within 24 hours. Failure to comply transforms the detention into an illegal arrest regardless of the original justification. The ruling reinforces Article 22(2) of the Constitution and Section 57 of the CrPC, making the 24-hour rule a mandatory screening mechanism, not a procedural formality.

The judgment operationalises two parallel guarantees that have coexisted in Indian law since 1950 but were rarely enforced with equal rigour.

Article 22(2) of the Constitution states that every arrested person must be produced before the nearest magistrate within 24 hours of arrest, excluding travel time. Section 57 of the CrPC (now Section 35 of the BNSS, 2023) mirrors this in statute. Together they create what the Court described as a mandatory screening process — the magistrate is not a rubber stamp but an independent authority whose role is to decide whether continued custody is justified.

The critical doctrinal move in Sujit Das is the Court's characterisation of non-compliance: keeping a person beyond 24 hours without magistrate production does not merely violate procedure — it retroactively converts the original detention into an illegal arrest. This matters because an illegally arrested person has the right to be released immediately and cannot be remanded under Section 167 CrPC.

The judgment also distinguishes arrest from detention. Arrest is a formal legal act with defined consequences. Informal detention — holding someone for 'questioning' or 'verification' — without following arrest procedure is constitutionally impermissible. Police cannot avoid the 24-hour clock by labelling custody as something other than arrest.

For CLAT PG, this connects directly to the bail and custody framework: the magistrate's power to remand under Section 167, the outer limit of 15-day police custody, and the right of the accused to be informed of grounds of arrest under Article 22(1).