falsus in uno falsus in omnibus
The maxim says that if a witness lies on one point, the whole of his testimony should be rejected. Indian courts have repeatedly held that it is not a rule of law in India and is at most a rule of caution. Almost every witness embellishes something, and rejecting all of a witness's evidence for one falsehood would let many guilty persons go free.
The court's duty is to separate the grain from the chaff: to accept the part of the testimony that is reliable and corroborated, and reject the part that is false. Only where truth and falsehood are so mixed that they cannot be separated is the whole evidence discarded. The Supreme Court restated this in Gangadhar Behera (2002).
Example
Rejecting the maxim falsus in uno falsus in omnibus, the court accepted the eyewitness's account of the stabbing though it disbelieved his claim about the time.
In Indian law
See also
hostile witness · interested witness · corroboration · witness