Essential legal maxims every layman should know.

These are few legal maxims that should be known by every layman, to enhance their knowledge about legal field and precedents.

A legal maxim is an established principle or proposition of law or legal policy that is usually stated in Latin form. Most of these are originated from the medieval era in European states that used Latin as their legal language. These principles guide courts all over the world in applying the existing laws in a fair and just manner to enable the court in deciding issues before it. Such principles don’t have authority of law but when court applies the maxims in deciding issues of law or the legislature incorporates such maxims while framing laws, they take the form of law and form the basis of sound judgements.

Important legal maxims everyone should know 

1. A fortiori

  • Literal meaning :- From Stronger
  • Interpretation :- An a fortiori argument is an “argument from a stronger reason” , meaning that because one fact is true, that a second related fact must also be true. If something less likely is true then something more likely will definitely be true. It suggests that an argument bases on another argument so strong as to make it unanswerable.

For example, “Shanky died on 25th may, therefore, a fortiori, Shanky did not kill Roy on 27th may.

  • Cases based on this Maxim :-
  • In Bobby v. Hook, the court held that “What the supreme court has said of state requirements is a fortiori true of standards set by private organisations.”
  • In Richmond v. J.A Croson Co., the court held “that congress may identify and redress the effects of society-wide discrimination does not mean that, a fortiori, the state and their subdivision are free to decide that such remedies are appropriate.”

2. Ab Initio

• Literal meaning :- From the beginning.

• Interpretation :- This means that something is valid or applicable from the very start or the beginning.

For Example :- A fact , an act , a document. It is often used as part of the phrase “void ab initio,” means an act that was void from the beginning. If any person holds a immovable property and he comes to know that some other person has registered a sale deed or some other deed then that person can file a suit for declaration and consequential reliefs. If heis satisfied that this is his property only and the other person has no title over it then he can leave it as that deed is void ab initio. The other person clamming will have to prove.

• Cases based on this Maxim :-
o Satya Pal Anand v. State of M.P. And Ors on 25 August, 2015, In this extinguishment ded as well as the subsequent sale deeds void ab initio with a further direction to the respondents to record the cancellation.

o The Indian Golf Union and Ors. V. West Bengal
Golf Society and Ors on February , 2020
, In this Supreme Court said that the arbitrator agreement in the new contract is linked to that new contract and the jurisdiction of the arbitrator to decide on his own jurisdiction under the arbitration agreement in the new contract cannot conceptually jump backwards to allow him/her to decide if the older contract has been replaced. Therefore, the arbitrator’s jurisdiction to be able to decide on his own jurisdiction when the dispute is that the new contract is void ab initio must reside in the arbitration agreement contained in the old contract.

3. Actori incumbit onus probandi

• Literal meaning :- Burden of proof is on the plaintiff.

• Interpretation :- A plaintiff to a legal action must prove his or her case to win the lawsuit against the defendant. The Plaintiff is obliged to submit to the court all the proofs that they have against the defendant to justify their claim.

For Example :- Just suppose that A have physically assaulted B, so B files a complaint against A. Now B will have to prove that A has physically assaulted him to support his claim as burden of proof lies on plaintiff.• 

Cases based on this Maxim :-
o M. Balakrishnan V. Tmt. Jeeva Mercy Kamla on July, 2010, here the initial burden is always on the landlords to prove the wilful default in payment of rent by tenant and if there are specific pleas like adjustment of advance etc. by the tenant, then it is for the tenant to proof the same. But in this case, tenant wasn’t able to prove that he gave advance of 30k as he didn’t had any documentary evidence. Hence, in this view of the matter , a fortiori the analysis of evidence and the ultimate conclusion arrived at by both the courts below, in revision, cannot be interfered with, as they decided the matter au fait with law and au courant with facts.

o State of U.P. V. Prem & 3 Ors. On 6 September, 2021, It is the fundamental in criminal jurisprudence that every person is presumed to be innocent until proven guilty, for criminal accusations can be hurled at anyone without him being a criminal. The suspect is therefore considered innocent in the interregnum between accusation and judgement. History reveals that the burden of proof is on the accuser. Roman law coined the principle of actori incumbit (onus) probatio (the burden of proof lies on plaintiff) i.e,. presumed innocence of the accused.

In Woolmington V. Director of Public Prosecutions [1935] AC 426 (HL), the House of Lords held that the duty of prosecution to prove the prisoner’s guilt was the “golden thread” throughout the web of English Criminal Law. Today, Article 11 of the universal Declaration of Human Rights, Article 14 of the International Covenant on Civil and Political Rights and Article 6 of the European Convention on Human Rights all mandate presumption of innocence of the Accused.

4. Actus Reus Non Facit Reum Nisi Mens sit Rea

• Literal meaning :- Conviction requires proof of criminal act
and intent.

• Interpretation :- An act dosen’t makes the person guilty unless their mind is also guilty or they have a criminal intent. If the physical act (actus reus) is not accompanied by the mental state (mens rea), it would not constitute a crime in itself. Therefore guilty mind, which is the intention of a person to commit a crime is crucial in proving their guilt in specific crime.

For Example :- Just suppose you threw a brick to move it aside from the road and it hit somebody, your intention wasn’t to hurt anyone but the physical hurt happened (actus reus) without any intention to hurt that is guilty mind (mens rea). In this case, the absence of guilty mind would prevent it from constituting severe crime.

• Cases based on this maxim :-
o State of Rajasthan V. Shera Ram @ Vishnu Dutta on 1 December, 2011

To commit a criminal offence, mens rea is generally taken to be a essential element of crime. It is said furiosus nulla voluntus est. In other words, a person suffering from mental disorder cannot be said to have committed crime as he does not know what he is doing. For committing a crime, the intention and act both are taken to be the constituents of the crime, actus non facit reum nisi mens sit rea. Every normal sane human being is expected to posses some degree of reason to be responsible for his/her conduct and acts unless contrary proved. But the person who is mentally ill cannot differentiate between wrong and right and also he remains unaware of the consequences of his act. The person who is willing to take this plea needs to prove that they are mentally ill, experts advices are taken and their checkup needs to be done, once it is proved that they are ill then only they get this relief .

o Krishna Lal And Anr. V. The state of M.P, on 18 August, 2017

In this case, also they said that
accused was mentally unstable, but for the same facts must be proved with potential documents validating insanity. Then the crucial time comes that whether this should be given as a defence or not, then it is looked on the character of crime. The accused was punished for the crime, he didn’t get to take the plea of insanity.

5. Volenti non fit injuria

• Literal meaning :- No injury can be done to a willing person.
• Interpretation :- This maxim says that a person who is willing to take the risk or is aware of the risk, that it can cause him harm in one way or other yet agrees to do the work cannot claim anything if injury happens because he was aware of the risk.

For example :- If you go for bungee jumping, and signs a waivers agreement then in case of any injury you won’t be
able to claim compensation or sue them.

• Cases based on this maxim :-

Morris V. Murray [1930] 3 All ER 801 (court appeal)
Volenti was held to the passenger, who accepted a lift from a drunk pilot. The pilot died in the resulting crash and the passenger who was injured, sued his estate. Although he drove the pilot to the airfield (which was closed at that time) and helped him turn the engine and tune the radio, he argued that he did not freely and voluntarily consent to the risk involved in flying. The court of appeal held that there was consent: the passenger was not so drunk as to fail to realise the risk of taking a lift from a drunk pilot, and his actions leading up to the flight demonstrated that he voluntarily accepted those risks.

Haynes V. Harwood [1935] 1 KB 146, this was a case in which a policeman was able to recover damages after being injured restraining a boulting horse: Here the injured person was a policeman, it was his moral duty, social responsibility and was also duty bond to protect people. Hence, he restrained the horse and got injured in the process, he didn’t voluntarily agreed for that damage or risk but fulfilled his responsibility and obligation. In this case the court of appeal affirmed a judgement in favour of the policeman who had been injured in stopping runaway horse with a van in a crowded street, the policeman was on duty and not on streets.



There are a lot of legal maxims that should be known even by layman. Here in this article we have discussed five among them. We came to know that how these maxims can help with the judgements, cases and also how they are referred. Maxims are very important part of our legal system, and are used with wisdom.

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