Habeas corpus is the principal means under the common law for the protection of personal liberty. ’Habeas Corpus’ literally means “to have a body of”. It allows a prisoner to indicate that his or her constitutionally guaranteed rights to fair treatment in a trial have been infringed upon. The writ of habeas corpus primarily acts as a writ of enquiry; it is issued by the courts to ascertain the grounds of detention of an individual. Therefore, it acts as a procedural safeguard against the law enforcement authorities, specifically their power to take into custody.

When Article 21 was suspended, it was held in Addl. District Magistrate, Jabalpur v. Shukla 1976 AIR 1207, , that an order of preventive detention could not be challenged even if it violated the parent Act (i.e, the Act relating to preventive detention). The 44th Amendment, 1978, has provided that Article 21, relating to personal liberty cannot be suspended even during an emergency. In this way, personal liberty has been strengthened and the writ of habeas corpus retains its potency even during an emergency.

Illustration: A is wrongfully detained by B, a police officer. A writes to the High Court regarding the same. The High Court summons B with A and asks the grounds for detaining A. If B fails to provide a valid ground or justification for A’s detention, A will be free to go.

The scope and extent of this writ were explained by the Supreme Court in State of Maharashtra v. Bhaurao Punjabrao Gawande  (2008) 3 SCC 613;. The Court stated that the writ of habeas corpus has been described as a great constitutional privilege or the first security of civil liberty as it provides a prompt and effective remedy against illegal detention. By the use of this writ, the Court directs the authority which has detained a person to produce the body of the person before the Court so that it can enable the validity, jurisdiction or justification of the arrest or detention.

This Writ is very important for the personal liberty of the citizens because if this Writ is not provided by the Constitution a person can be unlawfully restrained or detained by any authority and it will be a clear violation of the personal liberty of the citizens. Even though the purpose this Writ is to prevent a person from being detained but it will be applicable only when the detention or restraint is unlawful. If the Court finds the grounds for detaining to be justified then this Writ cannot be issued. Also, if the Court orders the detention of a person then it does not amount to unlawful detention and this Writ cannot be issued.
This Writ can be applied not only by the person who is detained but it can also be done by some other person on behalf of the detained person.

Rules regarding the Writ of Habeas Corpus

The following are the rules related to the writ of Habeas Corpus:
The applicant should be in custody of another Usually, the detained person and his family members are allowed to file an application for habeas corpus but the court has also allowed such application by strangers if it is done in public interest. The manner prescribed for filing this writ is not necessary so both formal and informal applications in respect of the writ is accepted by the Courts. For e.g. a writ application can also be made by postcard. In the case of Sunil Batra v. Delhi Administration (1978) 4 SCC 409, the Supreme Court had accepted the application made through a letter by a co-convict (a stranger) due to the inhuman treatment of prisoners. In this case, the letter was accepted
Writ of Habeas Corpus was issued.
A person cannot make the application for the Writ successively to different judges of the same court. Thus, if an application is rejected by one judge, the same application cannot be made to another judge of the same court and if it is done, such an application will be rejected because of the principle of res judicata.
This Writ will apply in case of an arrest made by the police when all the formalities and procedures which are required to be followed are not followed. For example – the requirement of presenting the arrested person before a magistrate or the officer in charge of the police station. [Section 56 of CrPC]
In Kanu Sanyal v. District Magistrate 1974 AIR 510 SCR , while enunciating the real scope of writ of habeas corpus, the Supreme Court opined that while dealing with a petition for writ of habeas corpus, the court may examine the legality of the detention without requiring the person detained to be produced before it.
In Sheela Barse v. State of Maharashtra 1983 SCC 337 , while relaxing the traditional doctrine of locus standi, the apex court held that if the detained person is unable to pray for the writ of habeas corpus, someone else may pray for such writ on his behalf.
In Nilabati Behera v. State of Orissa 1993 SCC 581 , the Orissa police took away the son of the petitioner for the purposes of interrogation & he could not be traced. During the pendency of the petition, his dead body was found on railway track The petitioner was awarded compensation of Rs. 1, 50,000.

Conclusion:

the right to individual freedom The most fundamental human rights are those protected by several human rights conventions and Article 21 of the Constitution. A person’s right to habeas corpus, which literally translates as “to produce the body,” protects them from being arbitrarily and illegally detained. Whether the person has been arrested in accordance with the legal process is determined by the habeas corpus petitions. One of the five writs by which a person may request the Supreme Court or the High Courts to uphold his fundamental rights is habeas corpus.

The writ of habeas corpus acts as a procedural tool by which executive, judicial, or other governmental limitations on human liberty are subjected to court scrutiny. It is a basic tool for defending an individual’s freedom against arbitrary and unlawful state action. The Writ of Habeas Corpus cannot be used to challenge earlier unlawful detentions since it is a remedy available to a person who has lost his personal liberty. But, as was done in the case of Rudul Shah v. State of Bihar, the Supreme Court has broadened the scope of this writ and now grants compensation not just for past unlawful detentions but also for loss of life.