Q: What is res ispa loquitur in tort ?

Ans: The well-established doctrine of res ipsa loquitur, in connection with proof of negligence, has been consistently followed in India.

(1) By applying this maxim, the burden of proof is shifted from the plaintiff to the defendant. Instead of the plaintiff proving negligence the defendant is required to disprove it. The maxim is not a rule of law. It is a rule of evidence benefiting the plaintiff by not requiring him to prove negligence.

(2) The maxim applies when- the injurious agency was under the management or control of the defendant, and (ii) the accident is such as in the ordinary course of things, does not happen if those who have the management use proper care. There must be no evidence of the actual cause of the accident.

(3) The rule that it is for the plaintiff to prove negligence is in some cases, of considerable hardship to the plaintiff, because it may be that the true cause of the accident lies solely within the knowledge of the defendant who caused it. The plaintiff can prove the accident but he cannot prove how it happened so as to show its origin in the negligence of the defendant. The hardship is avoided to a considerable extent by the maxim.

(4) The rule in Rylands v Fletcher is not an illustration of the mere principle of res ipsa loquitur. The liability arising out of the principle can be repelled by proof that the defendant was not negligent, whereas under the Rylands rule it is no defence to say that defendant took every possible precaution to prevent the escape of the injurious thing.

(5) The principle of res ipsa loquitur has no application where the circumstances in which the accident has taken place indicate that there must have been negligence but do not indicate as to who was negligent or when the accident is capable of two explanations. The story must be clear and unambiguous, and if it tells one of half a dozen possible stories, the maxim cannot be applied.  Also, the maxim does not apply when the facts are sufficiently known.

(6) Res ipsa loquitur is a common sense approach, not limited by technical rules, to the assessment of the effect of evidence in certain circumstances. It means that a plaintiff prima facie establishes negligence where

(i) it is not possible for him to prove precisely what was the relevant act or omission which set in train the events leading to the accident, but

(ii) on the evidence as it stands i.e. in the absence of any evidence from the defendant, it is more likely than not that the effective cause of the accident was some act or omission of the defendant.

"The maxim possesses no magic quality. Nor has it any added virtue, other than that of brevity, merely because it is expressed in Latin. When used on behalf of a plaintiff, it is generally a short way of saying, "I admit that the facts and circumstances which I have proved establish a prima facie case of negligence against the defendant." There are certain happenings that do not normally occur in the absence of negligence, and upon proof of these, a court will probably hold that there is a case to answer" [Morris L.J. in Roe v Minister of Health (1954) 2. Q.B. 66].

The maxim only shifts the onus of proof in that a prima facie case is assumed to be made but, throwing on the defendant the task of proving that he was not negligent. This does not however mean that he must prove how and why the accident happened; it is sufficient if he satisfies the court that he personally was not liable.