Oral testimony defines itself. It is the main reliance of the social diagnostician.

Documentary evidence is of many kinds, from formal documents of legal origin to the informal letters and writings of private persons. This subject of the uses of documents in case work is important enough to receive separate treatment in Chapter XIII, Documentary Sources. Suffice it to say here that it is a dangerous thing to trust to anyone's memory of a document; hence the rule of law, Always look at the document itself. If a tenant says, "The landlord sent me a notice to get out," call for the document. It may read: "If you do not pay your rent by next Monday, I will put you out," which is a different thing.

Expert evidence is one species of testimonial evidence. Its use signifies that the subject under consideration is one which is believed to need special skill in observing and judging. The advantage of expert testimony lies in the skill of the person giving it. A physician can tell to what extent certain children are suffering in health, whereas the social worker's opinion would be of little value. Hence, call in an expert whenever the judgment to be made is one that should not be based on ordinary experience. The disadvantage of expert testimony lies in the bias which specialists are apt to develop. A policeman is a specialist in crime; looking for the same thing always, his bias may become in time a marked tendency to expect to find it on every hand.

Character evidence needs no defining. Since the social worker seeks to discover the possibilities of bettering a client's situation, he naturally must look for those traits in the client and his family which may further or obstruct his purpose.

Years ago, when it often happened that the choice of treatment hardly went further than between the giving or refusing of coal and groceries, character evidence in social work was, as in the law courts, a mere generalized estimate, favorable or unfavorable, of an individual's characteristics. He was either worthy of relief or unworthy. The social worker's preoccupation, like the lawyer's, was with desert. Since on that basis the case worker's decision against any client's application for aid became invidious, the presumption, as a matter of justice, had to be in the client's favor. The burden of proof rested with those who gave evidence as to

unworthiness. One still sometimes finds this point of view in private agencies and public departments. As a rule, however, the case worker's interest is approaching an impartial study of personality, such as concerns itself not with the meting out of punish'ment or reward (the offering of almshouse or outdoor relief, for example) but with the determining of all traits, whether in their good or their bad aspects, as they affect the possibility and the method of social reconstruction. The successful outcome of case work is nowhere more dependent upon flexibility of method than in the study of personal traits. The choice of method being wide, and there being, generally speaking, no presumption in favor of one diagnosis rather than another, the social case worker, like the physician, has little call to consider the "burden of proof." Nevertheless, since the worker in his effort to arrive at an understanding of a client's personality must be free to take into account not only hearsay evidence but, with due precautions, even rumor, he may find it sometimes necessary to guard against his own infirmities of judgment by placing, as already suggested, the burden of proof with regard to his client's less admirable traits upon those who give this unfavorable testimony.

The relative importance of the distinctions made in this chapter is in many ways greater to the lawyer, historian, or scientist, than to the social worker. The conspicuous thing which the social case worker can learn from the lawyer is the risks involved in the various types of evidence, while from the historian he can learn the importance of a rigorous examination of sources of information as to their trustworthiness. From physician and psychologist social work has more to learn than from either lawyer or historian, inasmuch as science, unlike law or history, can throw direct light on the social needs and possibilities of the case worker's clients.

SUMMARY OF THIS CHAPTER

1. Social diagnosis is the attempt to arrive at as exact a definition as possible of the social situation and personality of a given client. The gathering of evidence, or investigation, begins the process, the critical examination and comparison of evidence follows, and last come its interpretation and the definition of the social difficulty. Where one word must describe the whole process, diagnosis is a better word than investigation, though in strict use the former belongs to the end of the process.

2. A controlling condition in social diagnosis is its relatively inelastic time limit -as compared, that is, with other forms of social inquiry. This does not mean that a social diagnosis cannot be revised; often it must be. Another controlling condition is the beneficent action always in view.

3. The word fact is not limited to the tangible. Thoughts and events are facts. The question whether a thing be fact or not is the question whether or not it can be affirmed with certainty. The gathering of facts is made difficult by faulty observation, faulty recollection, and by a confusion between the facts themselves and the inferences drawn from them.

4. Real evidence is the very fact at issue presented to our senses. Testimonial evidence is the assertions of human beings. Circumstantial evidence is the catchall; it includes everything which is not the direct assertion of a human being-the assertion, that is, which if true would establish the point at issue.

5. The three classes of evidence which are of general application may be distinguished by the way in which we make inferences from them. In real evidence no inference is needed; in testimonial evidence the basis of our inference is a human assertion; in circumstantial evidence the basis of our inference may be anything at all.

6. There is an important distinction in testimonial evidence between the evidence of one who says he saw or heard the supposed fact himself, and that of one who asserts it only from what others have told him. The latter is hearsay evidence. It should be relied on with caution, and a very necessary practice in interviewing witnesses is to discover the extent to which their assertions are founded on observations or on mere rumor.

7. There is another important distinction in evidence between direct and indirect evidence. Circumstantial evidence is always indirect and characteristically cumulative. In direct evidence, the only tests of trustworthiness needed are those usually applied to human traits, such as honesty, bias, attention, memory, suggestibility, etc.

CHAPTER IV

TESTIMONIAL EVIDENCE

FTER an historian has established the genuineness and

A

authorship of a document, his next care is to discover the

competence and bias of the man who made it; to go back, in short, to the testimonial evidence, the human assertions, on which the document is based. The following passage summarizes many of the queries suggested by Langlois and Seignobos1 in their discussion of the tests of an author's good faith and accuracy. Questions of legal competency aside, it will be seen that, with slight variations, these tests would apply to the competence and bias of any witness. They are most suggestive in the field of social work and deserve the case worker's careful consideration.

Good Faith. Were there any practical advantages to be gained by the witness who made the statement in its present form? Had he an interest in deceiving? What interest did he think he had? (We must look for the answer in his tastes and ideals, not in our own.) If there was no individual interest to serve, was there a collective interest, such as that of a family, a religious denomination, a political party, etc.? Was he so placed that he was compelled to tell an untruth? Was some rule or custom, some sympathy or antipathy, dominating him? Was personal or collective vanity involved? Did his ideas of etiquette, of what politeness demanded, run counter to making a perfectly truthful statement? [We do not know a man at all until we understand the conventions that form so large a part of the moral atmosphere which he breathes.] Or again, has he been betrayed into telling a good story, because it made an appeal to the artistic sense latent somewhere in all of us?

Accuracy. Was the statement an answer to a question or a series of questions? (It is necessary to apply a special criticism to every statement obtained by interrogation.) What was the question put, and what are the preoccupations to which it may have given rise in the mind of the person interrogated? Was the observer well situated for observing? Was he possessed of the special experience or general intelligence necessary for understanding the facts? How long before he recorded what he observed? Or did he record it, like some newspaper accounts of meetings, before it happened? Finally, was the fact stated of such a nature that it could not have been learned by observation alone?

1 Introduction to the Study of History, p. 165-176.

Like the historian, the case worker must have for the weighing of the evidence with which he deals a clear understanding of the two factors which condition the value of testimony; namely, (1) the witness's opportunity to know the facts and the way in which he has used this opportunity-his competence, in short; and (2) those ideas or emotions of the witness which may prejudice his judgment-his bias.

I. THE COMPETENCE OF THE WITNESS

Case workers heed the competence of a witness only in an unavowed and hit-or-miss fashion. Their daily experience it is true teaches them to take roughly into account the witness's opportunity to know the facts. For instance, they frequently find that the person referring a client for care thinks he has had ample opportunity to know the client's affairs when the reverse is the case.

A charitable woman asked relief for a capable widow whom she said she had known well for years. It appeared, however, that she did not know how many children were at home, whether the oldest son was working, what were the woman's habits as to drink, what the family income was, or whether, in fact, they needed aid at all. She had not been to the home of this family for several years, and had taken the statement of need as the widow gave it to her one day in church. The charitable woman was quite surprised, as her conversation with the secretary of the agency proceeded, to discover how superficial was her knowledge of any of the real circumstances of the widow's family life.

The social worker has to be on guard against this same risk in. consulting the relatives of a client. Some relatives know a great deal, and others, who think they know everything, really know very little.

An agency tried to interest fairly well-to-do relatives in the needs of a delicate man with a wife and several children. They were not responsive. They claimed they had already helped more or less, that they had burdens of their own, and that he was a loafer, a "poor shrimp," as one of the kin described him. It turned out that the man had locomotor ataxia, the result of syphilis. With this medical diagnosis, which explained to a considerable extent the man's ill success, the worker again appealed to the relatives, this time with good results.

This man's brothers and cousins had had no opportunity to learn the crucial point in his situation, and were therefore not competent witnesses as to his character for industry.

Ordinarily employers would not be competent witnesses as to a