Doctrine of Severability or also known as doctrine of separability is a legal provision which separates laws which are inconsistent with the fundamental rights thus It protects our Fundamental Rights.

The Doctrine of Severability is mainly based on article 13 of the Indian Constitution.

According to article 13:
Art.13(1) says:
All laws in force in the territory of India immediately before the commencement of this Constitution, in so far as they are inconsistent with the provisions of this Part, shall, to the extent of such inconsistency, be void.

Art.13(2) says:
The State shall not make any law which takes away or abridges the rights conferred by this Part and any law made in contravention of this clause shall, to the extent of the contravention, be void.

However, only the provisions of the legislation or act that are incompatible with the Fundamental Rights would be declared unlawful. In simple words, you must apply a filter to the concerned laws to see whether they protect fundamental rights. All of the laws that make it through this screening are valid. The legislation that are unable to pass must be separated.

This is what the Doctrine of severability is. Simply said, the notion of separation involves filtering and checking all acts. All laws that protect fundamental rights will be upheld. Those that are in violation of fundamental rights will be declared null and void. However, this can only be done if the part of the law that is in conflict with it, is completely isolated from the rest of the legislation. If the lawful and invalid parts are so closely intertwined that they cannot be distinguished, the entire legislation or act is declared invalid.

Genesis
The idea of Severability was used for the first time in the case Nordenfelt vs Maxim Nordenfelt Guns and Ammunition Company Ltd,1876. The plaintiff, an arms specialist, agreed to sell his business to the defendant on the condition that the plaintiff would never longer produce guns or other weapons for 25 years.

The contract, according to the court, violated public policy within a reasonable range. But the question was about severability, that whether the contract's irrational sections may be removed while the rest of the contract remained legitimate. Because the contract's unreasonable portion (Restraint of Trade) is severable, the court applied the blue pencil doctrine (similar to the Doctrine of Severability) and approved to strike out the first part of the agreement that " the plaintiff would not make guns or ammunition anywhere in the world " allowing the plaintiff to trade freely.

Important Cases In India
In A.K.Gopalan vs State of Madras (1950) AIR SC 27 ,which is a important and landmark judgement regarding the doctrine of severability. Section 14 of the Preventive Detention Act was challenged in this case. If a person is detained under this act, it was not allowed to reveal the reason for his imprisonment in court, according to Section 14.. When the doctrine of severability is applied and this Act is filtered out and only section 14 of the Preventive Detention Act is incompatible with fundamental rights as in article 22 of the indian constitution. Hence , in the judgement only one section of the act was repealed, while the rest of the act continued to be in effect.

In R.M.D.C. v. Union of India (1957) AIR SC 628, The applicant has filed a petition under Article 32 of the constitution, alleging that the respondents have violated his right according to article 19(2)by imposing a restriction on their ability to conduct business.

The respondents argued that Section 2(d) of the Prize Competition Act, 1955 does not apply to gambling competitions, but the petitioners countered that the definition of prize competition in Section 2(d) of the Act is quite broad, and it includes not only gambling competitions, but also other types of competitions.but also those in which success is dependent to a significant degree on luck.

According to the respondents, even if some parts of the Prize Competition Act were invalid, the valid parts should remain intact, and the entire Act should not be rendered null and void. The Supreme Court ruled that the claim of a violation of fundamental rights will be dismissed since gambling is not considered a commerce and so does not constitute a violation of fundamental right. The Supreme Court, after examining all factors, decided that the law of severability would apply in this case, with the invalid sections being removed from the Act and the legitimate portion being enforced. The court also established many guidelines on the doctrine of severability which may define invalid and valid parts in a law.

Guidelines established in the judgment)
If the lawful and invalid parts are so closely intertwined that they cannot be distinguished, the entire legislation or act is declared invalid.

the intention of the legislature will be the determining factor in deciding whether the provisions under check are valid or not.

If the valid and invalid parts of the statute are different and can be separated then the valid part which remains can form a complete code independent of the rest, will be checked. Then only it will be upheld.

Even if the provisions which are valid are separate from those which are invalid, but where supposed to be operated as whole together, the whole law will be void.

 When the valid and invalid parts of the Statute are independent and do not form any part of the Scheme but what is left after excluding the invalid part is so thin and curtailed as to be in substance different from what it was when it emerged out of the legislature then also the entire part will be rejected.

The severability of the valid and invalid provisions of the Statute does not rely on whether the provisions are enacted in the same or different sections.

If after the invalid part is obliterated from the statute, and what is left cannot be enforced without making the modifications and alterations, then the whole Act would be declared as void or else would lead to judicial legislation.

Relevance
Doctrine of Severability with its very own nature, widens the scope for judicial review and thus empowers the judiciary to strike out any unconstitutional provisions of the law. It enables the judiciary to evaluate pre-constitutional laws to check its consistency with the fundamental rights provided by the constitution.

This doctrine also restrains the legislature from make laws which may harm the fundamental rights of the citizens. The doctrine of severability plays a important role to protect the democracy in the country by protecting the fundamental rights of the citizens.

Personal Opinion
The doctrine of severability is a important element in the Indian Constitution that protects every citizen's fundamental rights. It is a litmus test for validating any law that violates fundamental rights, whether passed by the current parliament and legislative assembly or before to the establishment of the Constitution. This approach is very appealing because it safeguards the entire statute from the consequences of any defective provisions.

If any provision of law violates a fundamental right and its presence has no major effect on the functioning of the statute, the Court may hold that provision to be void under this doctrine, while the entire statute remains in effect. This idea applies to every legal component of government at all times. the very core idea of doctrine of severability is to separate rightful and valid parts of a law from invalid and unconstitutional ones. Thus is is very important to clearly distinguish valid and invalid provisions of a law.

The guidelines made in R.M.D.C vs Union of India are very much precise and will be helpful to clearly filter out unconstitutional laws. The doctrine of Severability has empowered our judicial system and has enabled it to critically analyse the validity of laws in accordance to the fundamental rights of the citizens. Thus this doctrine has a major role in upholding the democracy of the country by upholding the fundamental rights and giving it foremost importance in the judicial as well as legislative system in India.

Sources:

• Nordenfelt vs Maxim Nordenfelt Guns and Ammunition Company Ltd- https://en.wikipedia.org/wiki/Nordenfelt_v_Maxim_Nordenfelt_Guns_and_Ammunition_Co_Ltd
• A.K.Gopalan v. State of Madras- https://indiankanoon.org/doc/1857950/
• R.M.D.C. v. Union of India - https://indiankanoon.org/doc/725224/
• http://www.legalservicesindia.com/law/article/940/10/Doctrine-of-Severability
• https://indiankanoon.org/doc/134715/