Rulings on Questioned Documents the papers he found, for instance, that the disputed writing was made by a person holding a stub pen in his left hand at an angle of seventy-five degrees, and producing characters of a rolling design, while the writer of the standards used a sharp pen with his right hand, at an angle of one hundred and twenty degrees, and produced sharp angular characters; and where, because of that difference, in addition to numerous others of similar natures that he also mentioned, such witness is of opinion that different persons wrote the two sets of writings, nevertheless the witness did not testify to any facts. 6. Qualification of Witness. A lay witness "acquainted" with a man's genuine signature, and claiming to have an "exemplar" thereof in his mind, so that, by a comparison of such exemplar with a signature before him, the witness can tell whether or not such signature is genuine, cannot be required to establish his qualification by indicat ing any of the characteristics of such exemplar. An expert witness must have some knowledge of a language as a language, and not as a mere collocation of marks and letters, in order to pass on a writing in such language, even though the witness is entirely competent to pass on mere marks and letters themselves. 7. Cross-Examination. A lay witness "acquainted" with a man's genuine signature, and claiming to have such an "exemplar" thereof in his mind as will enable him to deter mine from inspection whether or not a signature submitted is genuine, cannot Philadelphia, December, 1911.
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be required to pass on such signature until he has seen also the rest of the paper. An expert witness may not supple ment his categorical answers by any explanations or qualifications, even though the truth requires it. 8. Self-Incrimination. The alleged forger may be required on cross-examination to write the words alleged to be forged, to be used in the case, even though it be a criminal pro ceeding against himself. 9 Aids to the Jury. Admittedly correct photographs of the writings are inadmissible, where the writings themselves are present or when the photographs are made on a trans parent background. The jury will not be furnished with any instrument to assist them in examin ing the writings in the jury room. 10. Comparisons by Counsel. Where counsel in addressing the jury proposes to compare the writings in the case for the benefit of the jury, by the aid of a scientific instrument, he may first be required to submit to a crossexamination regarding such instrument. It is reassuring, indeed, that the fore going rulings cover but twenty-four points; but, though their number is comparatively small, the radical nature of most of them is so striking as to make their avoidance of great importance. If it be true that we profit most by the mistakes we make, these rulings ought to be profitable to the profession out of all proportion to their numbers, and may it be so.
