The probative value of all honestly given testimony depends, naturally, first upon the witness's original capacity to observe; second, upon the extent to which his memory may have played him false; and third, upon how far he really means exactly what he says. This is just as true of testimony in cases of so-called circumstantial evidence as in cases where the evidence is direct, for the circumstances themselves must be testified to by witnesses who have observed them, and the authoritativeness of everything these witnesses have to say must lie in their ability to see, remember, and describe accurately what they have seen.

The subject of perjury is so distinct and far-reaching that it deserves separate consideration. The crime is easy to commit and difficult to establish by competent proof, for it is a highly technical offence and one which juries seem to find it easy to condone. The brother or friend of the accused has but to take the stand and swear to an alibi and lo! he is free. The chance of detection is small in comparison with the immediate benefit secured, while the temptation to swear falsely must, at least in the case of the immediate family of the prisoner, often be overwhelming. Where convictions for perjury are secured heavy sentences are invariably imposed and a wholesome apprehension instilled into the hearts of prospective witnesses, yet the amount of deliberate false swearing in our criminal courts would be inadequately described as shocking. To estimate its quantity would be difficult if not impossible, for it varies with the character of the case and the nature of the defence. When the latter is an alibi the entire testimony for the prisoner is frequently manufactured out of whole cloth, and it is probably not very wide of the mark to say that anywhere from a quarter to seventy-five per cent of the testimony offered by the defendant's witnesses upon the direct point in issue in the ordinary run of criminal trials is perjured.

Yet a careful scrutiny of even the honestly given testimony in such cases gives rise to the belief that the amount of strictly accurate evidence adduced is relatively small, so small as probably to stagger the credulity of the layman and to give the lawyer ground for reflection. It must be borne in mind, however, that this refers to criminal trials only and to testimony of a character closely relevant to the issue.

The first consideration is how far the witness was originally capable of receiving correct impressions through his senses. Naturally this depends almost entirely upon his physical equipment and the keenness and accuracy of his general observation, both of which are usually evidenced to a considerable degree by his appearance and conduct upon the stand.

Children are proverbially observant, and make remarkable witnesses, habitually noticing details which inevitably escape the attention of their elders; while various classes of persons by reason of their professional requirements are, of course, better qualified than others to observe certain facts or conditions, as a gem merchant the shape and cutting of a diamond, or a doctor the physical condition of a patient.

Witnesses are often honestly mistaken, however, as to their own ability to observe facts, and will unhesitatingly testify that they could hear sounds and discern objects at extraordinary distances. Lawyers frequently attempt to induce aged or infirm witnesses to testify that they could hear plainly what was said by the defendant, in an ordinary tone, at a distance, say, of forty feet. The lawyer speaks in loud and distinct tones during the preliminary examination, and then gradually drops his voice to that usually employed in speaking, in the hope that the witness will ask him to repeat the question. This ruse usually fails by reason of the fact that the lawyer, in his anxiety to show that the witness could not possibly hear the distance claimed, lowers his voice to such an extent that the test is obviously unfair.

For similar reasons counsel often call upon such witnesses to state the time by the clock which usually hangs upon the rear wall of the court-room. A distinguished but conceited advocate, not long ago, after securing an unqualified statement from an octogenarian, who was bravely enduring cross-examination, that he "saw the whole thing as if it had occurred ten feet away," suddenly challenged him to tell the time by the clock referred to. The lawyer did not look around himself, as he had done so about half an hour before, when he had noticed that it was half after eleven. The old man looked at the clock and replied, after a pause, "Half-past eleven," upon which the lawyer, knowing that it must be nearly twelve, turned to the jury and burst into a derisive laugh, exclaiming sarcastically, "That is all," and threw himself back in his seat with an air of having finally annihilated the entire value of the witness's testimony. The distinguished practitioner, however, found himself laughing alone. Presently one of the jury chuckled, and in a trice the whole court-room was in a roar at the lawyer's expense. The clock had stopped—at half-past eleven.

The professional actor upon the stage presents the illusion of nature by exaggerating those details of action which ordinarily would escape the attention of the observer.

In daily life we are quite as likely as not to be deceived by what we have seen, and this fact is so familiar to jurors that they are apt to distrust witnesses who profess to have seen much of complicated or rapidly conducted transactions. They want the main facts stated convincingly. The rest can take care of themselves. The extraordinary extent to which the complex development of modern life has dwarfed our powers of observation is noticeable nowhere more markedly than in the court-room. Things run so smoothly, transportation facilities are so perfect, specialization is carried to so high a degree, and our whole existence goes on so much indoors, that it ceases to be a matter of note or even of interest that the breakfast is properly cooked and served, that we are whisked downtown (a little matter say of five miles) in ten or twelve minutes, that we are shot up to our offices through twenty floors in an electric elevator, that there is a blizzard or a deluge, or that part of Broadway has been blown up or a fifteen-story building fallen down. We pass days without paying the remotest attention to the weather, and forget that we have relations. Instead of walking home to supper, pausing to talk to our friends by the way, we drop into the subway, bury ourselves in newspapers, and are vomited forth almost without our knowing it at our front doorsteps. The multiplicity of detail deprives us of either the desire or the capacity to observe, and we cultivate a habit of not observing lest our eyes and brains be overwhelmed with fatigue. Observation has ceased to be necessary and has taken its place among the lost arts.

Compare the old days when a Greek could go to hear the "Œdipus," and on returning home could recount practically the whole of it from beginning to end for the benefit of the wife, who was not allowed to go herself, or even the comparatively recent period when the funeral oration over Alexander Hamilton could be reported in the "Evening Post" from memory.