Indian Legal System is sustained by the grundnorm' or Indian constitution, which collaborated with Democracy and Rule of Law to provide justice without any discrimination. The accused have a right for fair hearing and justice without biasness, which are the primary principles of natural justice viz. the rule against bias (nemo iudex in causa sua) and the right to a fair hearing (audi alteram partem). It is a duty of legal system to act fairly, with proper human treatment even with the accused.
As our society develops with the evolution our laws, customs, legislation and whole legal system advanced, where the concept of rights of accused came over as a basic part of human rights. every human being, in every society, is entitled to have basic autonomy and freedoms respected basic needs satisfied, because accused are also a human. Correspondingly, they have a certain right during the course of investigation, any enquiry or trial of offence with which he is charged and he ought to be ensured against discretionary or illicit arrest.
Our criminal system follows the well-established ethics or often-quoted adage which says, let the thousand of criminals be let out, but a single innocent should not be punished. For this our courts need to settle down the all cases to be proved beyond the shadow of doubt. The constitution of India grants equal rights and opportunities for every person. Article 21 i.e. right to life and personal liberty have been interpreted by our Apex court in broad manner in the light of rights that further reinforced our criminal system.
For better instance there are 25 different rights which are interpreted by the Hon'ble Supreme Court of India under different subheads of article 21. A broad range of rights are given under constitution like the right to compensation in case of violation of Article 21, the right of under trials against unreasonable and arbitrary handcuffing, right against custodial violence, right of fair and speedy trial, right to free legal aid, the right to consult counsel of his choice, the right against any form of cruelty or violence or any form of degrading treatment etc. have been interpreted and secured by the help of article 21 by our Apex court.
Article wise Rights given under Constitution of India:
Article 20 (1)- Rights against conviction or enhanced punishment under an\nex-post facto law. It also covers the Retrospective criminal legislation, which grants protection against arbitrary and excessive punishment to an accused person.  Every law that takes away or impairs a vested right is retrospective. Every ex post facto law is necessarily retrospective.
Article 20 (2)- Right of protection against double jeopardy or Nemo debet bis vexari which means No one should be tried twice in respect to the same matter.  
Article 20 (3)- Right against self -incrimination or nemo tenetur seipsum prodere which means No one is bound to accuse himself. This article grants protection against testimonial compulsion.
Article 20 (3) and Article 21- Right of Privacy & protection unlawful search and seizure. Even now the Narco analysis test, Brain Mapping test and Lie Detector test are violative of the Article 20(3) and 21. Personal autonomy`s importance should be recognized in the decision of individual.
Article 21: - Right of speedy trial is a fundamental right implicit in the guarantee of life and personal liberty enshrined in Article 21 of the Constitution.
Article22(1) and (2)- Right to be informed of the grounds of arrest and right to bail
Article22(1) and (2)- Right to consult and be defended by a lawyer of his own Choice 
Article22(1) and (2)- Right against illicit or unlawful arrest. Also, the victim of unlawful arrest or detention shall have enforceable right to compensation.
Article22(1) and (2)- Right to production before a Magistrate within 24 hours. Violation of the right which guaranteed under article 22(2) invalidate the prosecution of accused.
Criminal Procedural Provisions Which Relates The Rights Of The Accused
Rule of law established the set of principles or ideals, which reduces the friction and ensure an order in the society. Presumption of innocence is the essence of the rule of law, where no person should be convicted until his crime is proved by the court of law, adopted in our constitution under article 20 (1). Generally, the rights of accused are provided only where the warrant is issued against the accused. Going further with the rights enshrined in criminal law or Criminal Procedure Code (CrPC), 1973 and secured by our Apex court.
Pre-Trial Rights of Accused:
Right to know about the charges and accusations- Sections 50, 55 and 76 of CrPC gives right to accused or arrested person to know the details of the offence and grounds on which he is detained.
Right against arbitrary or unlawful arrest- Sections 41, 55 and 151 of CrPC gives right against any illicit arrest.
Right to be examined by Medical Practitioner- Section 54 of CrPC provides the most important right after arrest which is right to be examined by a medical Practitioner, which further reduce the chances of cruelty or misbehavior under the custody of police.
Protection against arbitrary or illegal detention in custody- Sections 56, 57 and 76 of CrPC reduces the chance to detain the accused illegally or arbitrary.
Right against unnecessary restraint- Section 49 of CrPC gives right of the arrested persons not to be subjected to unnecessary restraint.
Right to be produced before Magistrate- Sections 57 and 76 give right to accused to be presented in front of Judicial Magistrate within 24 hours of arrest.
Protection against unlawful or arbitrary searches- Sections 93, 94, 97, 100 and 165 of CrPC give right to accused that the police cannot search or violate the privacy of accused on a mere presumption of innocence. As per our law his property cannot be searched without warrant.
Right to get Bail- Sections 436, 437 and 439 also Sections 50 (2) and 176 of CrPC, these sections give right to be released on bail if arrested. Our criminal system follows a very neat or cardinal rule which says, bail is the rule and jail the exception. This helps in a smaller number of imprisonment and overcrowded jails.
Right to legal aid, free and expeditious trial: Sections 303 and 304 provide that an accused has a right to consultation of lawyer of his own choice as well as right to get legal aid at the expense of the State in certain cases.
Rights of the Accused during Trial:
Right to get copies of Documents- Section 307 of CrPC provides that it is right of accused to receive copy of police report and copies of other documents filed by the prosecutor in relation to the case.
Right to be present at the trial- Section 273 of CrPC gives right to accused to be present at the trial or all evidence taken in the presence of accused. Whenever his personal attendance is not possible then in the presence of his counsel.
Right to Cross-Examination- It's the privilege of the accused in criminal cases to be cross-examined by the examiner to demonstrate their honesty.
Post-Trial Rights of Accused:
These rights are totally dependent on the outcome of the trial, in the case if declared innocent then:
Accused have a right to get copy of judgement.
Accused may ask for police protection if there is a danger or threat to his life.
In the case if declared guilty then:
Right to file appeal- Accused have a right to file an appeal against his conviction in a higher court. CrPC contains elaborate provisions on appeals starting from Section 372 to Section 394.
Right to file revision- When the right to appeal is exhausted then the concept of review procedure called revision is applied. Section 397 to Section 405 of CrPC incorporate the powers of revision allowed to the higher courts, and the procedure to practice these powers. The revisional jurisdiction can be summoned where the decisions under court of law are horribly wrong.
Human Rights As Per International Covenant and United Nations:
Human rights are those minimal rights that every individual must have against the state or administrative authority. India being a member of United Nations Human Rights Council (UNHRC) and also of International Covenant on Civil and Political Rights (ICCPR) serve the sacred aim of humanity that All persons deprived of their liberty shall be treated with humanity and with respect for the inherent dignity of the human person, which is also stated in the article 10 of ICCPR. UNHRC provides minimum Rules for Protection of Prisoners and in chapter 4 it provides basic rights of the suspect and the accused viz. from article 54 to 71. In 1948, Universal Declaration of Human Rights, has perceived certain essential human privileges of an individual, including an accused.
Our apex court has already settled down by the way of judgment that speedy trial is in wide sweep and come under article 21 of the constitution. The reasoning behind the concept of speedy trial is to check the inordinate or unnecessary delay in trial of criminal cases, which further responsible for gross denial of justice and long incarceration of under trial prisoners or accused. The court has also made provision for legal aid at State cost obligatory in instances of poor and poverty stricken denounced under preliminary in criminal cases, for looking for bail and furthermore for defense at the time of trial.
Custodial Death Due To Physical Torture And Third Degree Is A Violation Of Law:
The Supreme Court held that use of physical torture and third degree method is a straight violation of Article 21 of constitution and directed the state to take strict actions and necessary steps to prevent it further.
Where human servitude and individual torment are included, to hold up is to vanquish. Where equity is in peril or opportunity is in chains the court isn't neutral and acts with delicate speed. Also in another landmark decision Hon'ble Supreme court held that cruelty, physical torture and assaults by a person who is supposed to protect it from is not acceptable. There can be no room for leniency for such inhumane behaviour.
The courts of law and judiciary system is to provide justice to the society. A person accused of any offence should not be punished until his crime is proved or justified by court of law. The primary and fundamental object of criminal system is to provide fair and speedy trial to accused without infringing any rights which are so secured by the constitution. An accused should give a chance to defend himself. But our sociological finding shows us that the actual scenario of justice is pretty different what we have in our norms and ideals of the legal system.
Justice delayed justice denied is the legal maxim which express that is totally unfair for the accused to suffer injury with less hope of resolution. Having said that, when we acknowledge the recommendation that in a law-based society the court framework assumes a vital job in observing that neither permit nor absolutism gets predominant, the troublesome undertakings of the court clearly gaze us in the face.
The apex court also established in may decision that the doctrine of personal liberty given under constitution would essentially expect that no arrest ought to be made only in light of the fact that is legal for the police to do as such. Except in the cases of heinous offences, an arrest must be avoided. Having said that, organization of criminal equity is concerned about a wrongdoing, which implies a demonstration considered by law to be hurtful to society as a rule despite the fact that its quick casualty happens to be a person.
Rao Shiv Bahadur Singh And Another v. The State of Vindhya Pradesh, 1953 AIR 394
Kedar Nath Bajoria v. The state of West Bengal, 1954 AIR (SC) 660
Rattan Lal vs State of Punjab, 1965 AIR 444
Maqbool Hussain v. The State of Bombay, AIR 1953 SC 325
Manu Sharma v. (NCT of Delhi), AIR 2010 SC 2352: (2010) 6 SCC 1.
M.P Sharma v. Satish Chandra [AIR 1954 S.C 300]
Yogendra Kumar Jaiswal v. State of Bihar, (2016) 3 SCC 183
Selvi and Ors. v. State of Karnataka, A.I.R 2010 S.C. 1974.
K. Vijaya Lakshmi vs Govt. Of A.P. Represented by its Secretary Home & Anr, (2013) 5 SCC 489
..... by dimple Sangeetha (legallydiviner.blogspot.com)