The trial Judge should take into consideration the demeanour of witnesses in the evaluation of evidence. Demeanour, which is outward or overt behaviour or manner of a witness, is the exclusive domain of the trial Judge. It includes all open habits and mannerisms of the witness. These ooze out from the body of the witness spontaneously and not tutored. Some of such body movements include a spontaneous positive or negative reaction to a question; shouting at a particular moment or the opposite action of a pretentious mum conduct; movement of part of the body, particularly the hands and the sudden change in the face arising either from anger or happiness, the latter resulting in either a smile or laughter. Another is a sudden remorse on the part of the witness, usually exhibited by refusal to look at the Judge or Counsel, or others in the court, but a sudden drop of the face in the witness box. There are quite a number of behaviours in the determination of demeanour which cannot be exhausted. I can stop with the above as the major conducts of witnesses. I should complete the picture by saying that as appellate judges are deprived of watching the demeanour of witnesses, trial Judges owe the administration of justice a big duty to arrive at the correct conclusion. Of course appellate Judges are not completely hopeless or helpless. They can watch the evaluation of demeanour by the Judge in the cold records.
— Niki Tobi, JSC. Buhari v. INEC (2008) – SC 51/2008