An individual exercises certain rights that are conferred upon him either by the Constitution, statute or a contract.  A Right can be defined as an interest or a claim which gives the individual the power to control the act of others, i.e. to make someone commit or omit an act.

Now, the question arises when can these rights be exercised or waived off?

It is important to understand the Doctrine of waiver at this juncture. The doctrine of Waiver of rights is based on the premise that a person is his best judge and that he has the liberty to waive the enjoyment of such rights as are conferred on him by the State. However, the person must have the knowledge of his rights and that the waiver should be voluntary.

Waiving a right means that a person can no longer claim that right and is impeded to challenge the constitutionality of that law for the benefit of which, the right is waived off.

The doctrine is based on the principle that a person is the best judge of his own interests and when given full knowledge, he should decide for himself. In India, a person has the authority to waive off rights arising out of a contract or statute but cannot relinquish constitutional rights or rights guaranteed by the constitution itself.

Rights which are fundamental to well-being of a person are called Fundamental Rights. The Fundamental Rights are envisaged in Part 3 of the Constitution of India.
These are:

1. Right to Equality (Article 14 & 18)
2. Right to Freedom (Article 19 & 22)
3. Right against Exploitation (Article 23 & 24)
4. Right to Freedom of Religion (Article 25 & 28)
5. Cultural and Educational Rights (Article 29 & 30)
6. Right to Constitutional Remedies (Article 32)

The fundamental rights exist not only for an individual's benefit or well-being but are a matter of public policy. Rights which are part of public policy cannot be waived. Moreover, the Constitution imposes an obligation on the State to protect these rights.

Evolution of the Doctrine:

Shortly when the Constitution came into force the courts were met with the question of waiver of rights.

1. Behram Khurshed Pesikaka v. The State of Bombay, 1954:
   It was observed that the fundamental rights are based on such principles which are embodied in the preamble of the Indian Constitution. Fundamental rights are a matter of public policy and the same cannot be waived. The doctrine of waiver has no application on matters that are a part of constitutional policy
    
2. Basheshar Nath v. The Commissioner of Income Tax Delhi & Rajasthan & Another, 1959:
   The leading case till date on the Doctrine of Waiver is Basheshar Nath v. CIT where the majority expressed its view against the waiver of fundamental rights. It was upheld that it was not open to citizens to waive any of the fundamental rights. Any person aggrieved by the consequence of the exercise of any discriminatory power, could be heard to complain against it. The doctrine of Waiver does not apply to Indian Constitution, as Justice Bhagwati stated that …. Ours is a nascent democracy and situated as we are, socially, economically, educationally and politically, it is the sacred duty of the Supreme Court to safeguard the fundamental rights which have been for the first time enacted in Part III of our Constitution…
    
3. Olga Tellis & Ors vs Bombay Municipal Corporation:
   In this case, it was further held that there can be no estoppel against the Constitution. The Preamble of the Constitution states India to be a democratic republic and no citizen could barter away with fundamental rights.
    
4. Jaswantsingh Mathurasingh & Anr. v. Ahmedabad Municipal Corporation & Ors:
   The court held that everyone has the right to waive off legal right or privilege that is conferred upon him. For instance, in the case of a tenant-owner dispute, if a notice is issued and no representation is made either by the owner, tenant or sub-tenant, it would be a waiver of opportunity and that person cannot be allowed to turn around at a later stage.

Salient Features Of The Doctrine:
Intention:
It is an essential element as one must intend such Waiver. Waiver of right can either be expressed or implied. Express waiver is done in writing or giving a statement of waiver. Implied waiver is judged based on the conduct or act of a person.

Knowledge:
Knowledge here implies to the person waiving off rights must know of the nature of such rights and consequences of such waiver. It's not necessary to have absolute understanding of the right/privilege but be briefed about it.
 
Relevance:
The doctrine of waiver is of prime importance and its non-application on constitutional rights is a major check on powers of legislature. If the doctrine were to be applicable, it could make an individual waive his rights in lieu of some benefits provided by the State.

The doctrine is founded on justice and reason. It would be unfair and unjust to hear who alleges inconsistent facts. Allowing a person to first take benefit of the statute and then challenge its constitutionality is unreasonable. Moreover, it can be argued that ignorantia juris non excusat, a person alleging that he did not know about the unconstitutionality of the statute should not be excused.

Thus, it can be deduced that doctrine of waiver holds much importance and its unique characteristics ensure that no error of law takes place. Its applicability is justified and the landmark judgements delivered ensures that there are no conflict of views regarding it.

Conclusion:
In my personal opinion, rights are privileges that are conferred upon individuals for their well-being.  If such rights will be challenged and relinquished in a court of law, their subsistence is questionable. Fundamental rights also known as the Magna Carta of India, are contained in Part 3 of the Constitution of India.

Fundamental rights are a part of constitutional rights and public policy, thus, cannot be waived by an individual. This is apt as rights which are bestowed for the welfare of community if waived off according to the intent and knowledge of an individual will create confusion, chaos and can be misused for personal gain. Therefore, doctrine of waiver keeps the discretionary power of an individual in check.

Thus, we can conclude that doctrine of waiver and its scope is befitting and significant. It protects the rights of an individual and construes proper balance between personal liberty and social control.