Petitioner was convicted in the District Court for southern California of using the mails to defraud in violation of section 215 of the Criminal Code (18 USCA § 338). This Court granted certiorari, 282 U.S. 826, 51 S.C.t. 77, 75 L. Ed. -, October 20, 1930, to review a judgment of affirmance by the Court of Appeals for the Ninth Circuit, which upheld certain rulings of the trial court upon the evidence. 41 F.(2d) 157.
In the course of the trial the government called as a witness a former employee of petitioner. On direct examination he gave damaging testimony with respect to various transactions of accused, including conversations with the witness when others were not present, and statement of accused to salesmen under his direction, whom the witness did not identify. Upon cross-examination questions seeking to elicit the witness's place of residence were excluded on the government's objection that they were immaterial and not proper cross-examination. Counsel for the defense insisted that the questions were proper cross-examination, and that the jury was entitled to know 'who the witness is, where he lives and what his business is.' Relevant excerpts of the record are printed in the margin.
Later, the jury having been excused, counsel for the defense urged, as an 'additional' ground for asking the excluded questions, that he had been informed that the witness was then in the custody of the federal authorities, and that such fact might be brought out on cross-examination 'for the purpose of showing whatever bias or prejudice he may have.' But the court adhered to its previous rulings, saying that if the witness had been convicted of a felony that fact might be proved, but not that he was detained in custody.
The Court of Appeals, after stating that it is customary to allow cross-examination of a witness with reference to his place of residence, upheld the trial court, saying, page 160 of 41 F.(2d):
'The purpose of such evidence is to identify the witness and to some extent given proper background for the interpretation of his testimony. In this case, however, the counsel indicated his purpose to use the information for the purpose of discrediting the witness. It is part of the obligation of a trial judge to protect witnesses against evidence tending to discredit the witness unless such evidence is reasonably called for by exigencies of the case. A witness is not on trial and has no means of protecting himself. Here it was evident that the counsel for the appellant desired to discredict the witness, without, so far as is shown, in any way connecting the expected answer with a matter on trial. If it had been contended that the witness was in custody because of his participation in the transaction with which the appellant was charged, and if it was sought to show that he was testifying under some promise of immunity, it would undoubtedly have been prejudicial error to have excluded such testimony; but counsel avowed no such purpose, and indicated that the proposed question was merely in pursuit of a fishing expedition by which he hoped to discredit the witness. The witness was examined at great; length concerning his relation to the appellant and great latitude was accorded in that examination.'
Cross-examination of a witness is a matter of right. The Ottawa, 3 Wall. 268, 271, 18 L. Ed. 165. Its permissible purposes, among others, are that the witness may be identified with his community so that independent testimony may be sought and offered of his reputation for veracity in his own neighborhood, cf. Khan v. Zemansky, 59 Cal.App. 324, 327ff, 210 P. 529; 3 Wigmore, Evidence (2d Ed.) § 1368 I. (1)(b); that the jury may interpret his testimony in the light refiected upon it by knowledge of his environment, Kirschner v. State, 9 Wis. 140; Wilbur v. Flood, 16 Mich. 40, 93 Am. Dec. 203; Hollingsworth v. State, 53 Ark. 387, 14 S. W. 41; People v. White, 251 Ill, 67, 72ff., 95 N. E. 2036; Wallace v. State, 41 Fla. 547, 574ff., 26 So. 713; and that facts may be brought out tending to discredit the witness by showing that his testimony in chief was untrue or biased, Tla-koo-yel-lee v. United States, 167 U.S. 274, 17 S.C.t. 855, 42 L. Ed. 166; King v. United States (C. C. A.) 112 F. 988; Farkas v. United States (C. C. A.) 2 F.(2d) 644; see Furlong v. United States (C. C. A.) 10 F.(2d) 492, 494.