‘Bail’ connotes the process of procuring the release of an accused charged with certain offence by ensuring his future attendance in the court for trial and compelling him to remain within the jurisdiction of the court. The concept of bail has come under the scope of human rights since the UN declaration of Human Rights of 1948.
Bail has been defined by Black’s Law Dictionary as “the security required by a Court for the release of a prisoner who must appear at a future time”. It further says that, verb Bail means “to obtain the release of oneself or another by providing security for future appearance”
Bail therefore presupposes the deprivation of liberty of the person to be released and when he is released from such restraint or custody he is said to be released on bail.
Categories of Bail
These are the cases where grant of bail is a matter of course and right. In view of section 436 Cr. P.C. 1973 a person accused of bailable offence at any time while under detention without a warrant and at any stage of the proceedings has the right to be released on bail.  When the offence is bailable and accused is prepared to furnish bail, police officer has no discretion to refuse bail.
Non Bailable Cases:
If a person is accused of a non-bailable oﬀence, he cannot claim the grant of bail as a matter of right. But the law gives special consideration in favour of granting bail where the accused is under sixteen, a woman, sick or inﬁrm, or if the court is satisfied that it is just and proper for any other special reason to give rather than refuse bail [Section 437 (1) CrPC].
In case of an offence punishable with death or life imprisonment the person is not released on bail if the prima facie evidence makes it reasonable to consider him guilty. Also in case of such offences the person cannot be released on bail without giving an opportunity of hearing to the public prosecutor (Section 437 CrPC).
A person is not released on bail if the offence is a cognizable offence and he had been previously convicted of an offence punishable with death, imprisonment for life or imprisonment for seven years or more, or he had been previously convicted on two or more occasions of a cognizable offence punishable with imprisonment for three years or more but not less than seven years (Section 437(2) CrPC).
The accused is released on bail if there are not reasonable grounds for believing that the accused has committed a non-bailable offence pending further inquiry into his guilt.
Considerations by the Court while granting bail:
The provisions of CrPC regarding bail confer discretionary powers on the courts to grant bail to accused pending trial, since the jurisdiction is discretionary; it has to be exercised with great care and caution. The court is required to record in writing its reasons or special reasons for releasing a person on bail. The Supreme Court in various cases has laid down guidelines for the lower courts for exercising their discretion while granting bail.
In Kalyan Chandra Sarkar v. Rajesh Ranjan @ Pappu Yadav and Anr. in para 11 it was observed that “The court granting bail should exercise its discretion in a judicious manner and not as a matter or course. Though at the stage of granting bail a detailed examination of evidence and elaborate documentation of the merit of the case need not be undertaken, there is a need to indicate in such orders reasons for prima facie concluding why bail was being granted particularly where the accused is charged of having committed a serious offence. Any order devoid of such reasons would suffer from non-application of mind. It is also necessary for the court granting bail to consider among other circumstances, the following factors also before granting bail; they are:
(a) The nature of accusation and the severity of punishment in case of conviction and the nature of supporting evidence.
(b) Reasonable apprehension of tampering with the witness or apprehension of threat to the complainant.
(c) Prima facie satisfaction of the court in support of the charge.
Other factors to be considered by the court while granting bail are:
Whether the accused is likely to flee.
The fact of the accused being caught red-handed.
The fact of the accused being a repeat offender.
Whether the accused is willing to comply with the conditions imposed by the court.
The likely punishment to be imposed on the accused if punished.
The strength of the evidence against the accused.
The fact of previous commission of the offence by the accused during bail.
The period of imprisonment already undergone by the accused during the pendency of the trial.
Bail to under trials:
The issue of bail to under trial prisoners has been in debate because of the increasing under trial population in the jails approximating around 64.7% of the total prison population. The National Human Rights Commission has repeatedly given detailed guidelines regarding the release of under trials on bail. The personal liberty of a person can be deprived only when he is proved guilty otherwise it would be violation of his human rights. In Mantoo Majumdar v. State of Bihar the Supreme Court upheld the undertrials’ right to personal liberty and ordered the release of the petitioners on their own bond and without sureties as they had already spent six years awaiting their trial in prison. The Central Government and various State governments have requested the High Courts to release the under trials who are entitled to bail. Advocate Vijay Aggarwal had filed a petition asking the court to formulate a policy for the release of prisoners charged with offences carrying maximum punishment of 7 years of imprisonment. The petition demanded the release after one year imprisonment of the under trial. But the move was opposed by the Government which was against formulation of a general policy and demanded that the cases be dealt with based on their particular factual situation.
Section 167(2) Cr.P.C. requires the investigating agency to complete the job of investigation and file the charge-sheet within the time limit of either 60 or 90 days as the case may be on failure of which the accused would be entitled to be released on bail. But the current situation shows the disregard of the above condition laid down in the code.
 Nathurasu v. State, 1998 Cri LJ 1762 (Mad).  Ratilal Bhanji Mithani v. Asstt. Collector of Customs, AIR 1967 SC 1939  Dharmu Naik v. Rabindranath Acharya 1978 CrLJ 864 : Kanu Bhai v. State of Gujarat
1972 (B) Guj LR 748.
 (2004 (7) SCC 528)