27 Id. 630. Where a witness is sought to be impeached by proof of contradictory statements alleged to have been made by him, the time and place, and precise matter of the contradictory statements must be brought to the knowledge of the witness on cross-examination. Baker v. Joseph, 16 Id. 173; People v. Garnett, 29 Id. 622; People v. Devine, 44 1d. 452. And this rule applies to letters written by the witness. Leonard v. Kingsley, 50 Id. 628. See People v. Doyell, 48 Id. 85. If one side introduces evidence tending to show that a witness was suborned, the other side may introduce testimony to show the good character of the witness. People v. Ah Fat, 48 Id. 61. If a question is put to a witness which is collateral or irrelevant, his answer can not be contradicted by the party who asked the question, but is conclusive against him. People v. Bell, 53 Id. 119. Sec. 1102, n. 18, C. C. P. 2051, post, and notes.

28. Memory of Witness.-A book-keeper, called as a witness, has a right to refer to the books kept by him, to refresh his memory. Treadwell v. Wells, 4 Cal. 260. A witness may, while on the stand, refresh his memory by a reference to a written memorandum made by him at the time or soon after the occurrence which he is relating. People v. Cotta, 49 Id. 166.

29. Opinions of Witnesses.-The opinions of witnesses are generally admissible only when they relate to matters of science or art, or to skill in some particular profession or business. Hastings v. Steamer Uncle Sam, 10 Cal. 341. But a witness, though not an expert, who details a conversation had between himself and another, may also, in connection therewith, state his opinion, impression, or belief as to the state of mind of such person as these seemed to the witness at the time of the conversation. People v. Sanford, 43 Id. 29. There is no rule of law fixing the precise amount of experience or degree of skill necessary to constitute an expert. All that is open to inquiry and proof at the trial. The judge must, in the first instance, pass upon the admissibility of the witness; and then, if admitted, the jury judge of the weight and credit to be given to the testimony. The question is mainly one of fact, and it is only when there appears some error in law in determining the question of admissibility, or when there is no competent evidence to prove proper qualification of the witness, that the decision of the presiding judge is reversed on exceptions. Com. v. Williams, 105 Mass. 68. A physician, testifying as an expert, may give an opinion founded upon his reading and study alone. Taylor v. Railway, 48 N. H. 304; State v. Wood, 53 Id. 483. On a trial for forgery committed by altering a check, by extracting writing therefrom and writing new words or figures in place thereof, a witness, who is not called as a scientific expert, may testify as to the chemical effect a powder, found in the possession of the defendants, had on writing in a check similar to that by the alteration of which the forgery was committed, and the check upon which the effect testified to by the witness was produced may be exhibited to the jury. People v. Brotherton, 47 Cal. 388.

30. Privileges of Witness.-Where the answer of a witness would subject him to criminal punishment, he is not privileged from answering, on the ground that his answer would disgrace him, but solely on the ground that he is not compelled to criminate himself. Ex parte Rowe, 7 Cal. 184. A party to an action who becomes a witness in his own behalf has the same and no greater privileges than any other witness. He may refuse to answer a question when the answer would tend to degrade his character. People v..

Reinhart, 39 Id. 449. The privilege not to answer is personal to the witness, and is not in any sense the privilege of the party calling him. Clark v. Reese, 35 Id. 89. He must assert his privilege at the proper time, and it is not the duty of the court, independently of any objection on the part of the witness, to inform him that he is not obliged to criminate himself. People v. Hackley, 24 N. Y. 83; Com. v. Shaw, 4 Cush. 594. If he discloses a part of the transaction with which he was criminally concerned, without claiming his privilege, he must disclose the whole. He can not, after voluntarily testifying in chief, decline to be cross-examined on the ground that his answers may criminate or disgrace him. People v. Freshour, 55 Cal. 375; Norfolk v. Gaylord, 28 Conn. 309; People v. Carroll, 3 Park. Crim. R. 73; Com. v. Price, 10 Gray, 472. A defendant who offers himself as a witness waives his right to refuse to furnish evidence against himself, and is subject to an examination on all facts material to the issue. Com. v. Mullen, 97 Mass. 545. Where a statute provides that a witness shall be compelled to testify in certain cases, notwithstanding his testimony may tend to criminate himself, but that such testimony shall not afterwards be used against him, he may be compelled to so testify notwithstanding the constitutional provision that no person shall be compelled to be a witness against himself. The fact that detailing a precise account of the circumstances of a given crime would afford the prosecutor some facilities for fastening the guilt upon the actual offender makes no difference. People v. Hackley, 24 N. Y. 83. "The possession of the circumstances might point out to him (the prosecutor) sources of evidence which he would otherwise be ignorant of, and in this way the witness might be prejudiced. But neither the law nor the constitution is so sedulous to screen the guilty as the argument supposes. If a man can not give evidence upon the trial of another person without disclosing circumstances which will make his own guilt apparent, or at least capable of proof, though his account of the transactions should never be used as evidence, it is the misfortune of his condition and not any want of humanity in the law. If a witness objects to a question, on the ground that an answer would criminate himself, he must allege in substance that his answer, if repeated as his admission on his own trial, would tend to prove him guilty of a criminal offense. If the case is so situated that a repetition of it on a prosecution against him is impossible, as where it is forbidden by positive statute, I have seen no authority which holds or intimates that the witness is privileged. It is not within any reasonable construction of the language of the constitutional provision. The term 'criminal case,' used in the clause, must be allowed some meaning, and none can be conceived other than a proзecution for a criminal offense. But it must be a prosecution against him; for what is forbidden is that he should be compelled to be a witness against himself. Now if he be prosecuted criminally touching the matter about which he has testified upon the trial of another person, the statute makes it impossible that his testimony given on that occasion should be used by the prosecution on the trial. It can not, therefore, be said that in such criminal case he has been made a witness against himself, by force of any compulsion used towards him to procure, in the other case, testimony which can not possibly be used in the criminal case against him." Per Denio, J., in People v. Hackley, supra.

1322. Except with the consent of both, or in cases of crimi

nal violence upon one by the other, neither husband nor wife is a competent witness for or against the other in a criminal action or proceeding to which one or both are parties. [Amendment, approved March 30, 1874; in effect July 1, 1874.

1. Husband or Wife as Witness.-See C. C. P. 1881, subd. 1. A party to an action, by the examination of her husband as a witness on her behalf, waives her objection to his examination by the opposite party upon any of the issues in the action. Steinburg v. Meany, 53 Cal. 425. In ordinary cases proof that a man and woman cohabited a long time as husband and wife, mingled in society as such, and represented each other as such, is, in absence of evidence to the contrary, sufficient proof of a marriage between the parties. People v. Anderson, 26 Id. 129. A woman living with defendant as his wife, but not married to him, is a competent witness against him. People v. Alviso, 55 Id. 230. Declarations of a wife made to a third person are not admissible as evidence against her husband. People v. Simonds, 19 Id. 276. But evidence of acts and exclamations of the prisoner's wife at the time of the killing, and in his presence or hearing, are admissible. People v. Murphy, 45 Id. 143. When two parties are jointly indicted, but tried separately, the wife of one may be a witness for or against the other, if her husband can not be benefited or injured by her testimony. State v. Waterman, 1 Nev. 543.

1323. A defendant in a criminal action or proceeding can not be compelled to be a witness against himself; but if he offer himself as a witness he may be cross-examined by the counsel for the people as to all matters about which he was examined in chief. His neglect or refusal to be a witness can not in any manner prejudice him, nor be used against him on the trial or proceeding. [Amendment, approved March 30, 1874; in effect July 1, 1874.

be com

1. Defendant as a Witness. "No person shall pelled, in any criminal case, to be a witness against himself." Const. Cal., art. I, sec. 13; U. S. Const., Amendment 5. The right of defendant to be examined in his own behalf is one which he may exercise or not, and no presumption can be properly indulged in against him for his not doing so. People v. Anderson, 39 Cal. 703. The fact that defendant becomes a witness in his own behalf does not change or modify the rules of practice, with reference to the proper limits of cross-examination, and does not make him a witness for the state against himself. People v. McGungill, 41 Id. 429. Where defendant is examined as a witness in his own behalf, the prosecution is entitled to cross-examine him respecting an occurrence about which he tes tified in chief: 1. For the purpose of showing express malice; and 2. In order to lay a foundation to impeach his credibility. People v. Dennis, 39 Id. 625. If he become a witness in his own behalf, he has the same and no greater privileges than any other witness. He may refuse to answer a question when the answer would tend to degrade his character. People v. Reinhart, 39 Id. 449; People v. Johnson, 7 Pac. C. L. J. 168; People v. Beck, Id. 628. A defendant who becomes a witness in his own behalf and undertakes to state all that transpired between two points of time, may be asked on

cross-examination if he has omitted anything pertinent to the case, and his attention may be directed to the precise point by asking him if some specified thing did not occur. People v. Russell, 46 Id. 121. If defendant at the preliminary examination voluntarily becomes a witness in his own be half, and if it appear that his testimony there given was free from undue influence, it may be used against him on his subsequent trial. People v. Kelley, 47 Id. 125. The failure to become a witness in his own behalf is not a circumstance to be considered by the jury as tending to establish the guilt of defendant, and it is error to permit counsel so to argue against the objections of defendant. People v. Brown, 53 Id. 66; People v. McGungill, 41 Id. 429; People v. Tyler, 36 Id. 522; See also People v. McCauley, 45 Id. 146; People v. Rodundo, 44 Id. 538; People v. Bruzzo, 24 Id. 41. Sec. 688, n. 1.

CHAPTER III.

COMPELLING THE ATTENDANCE OF WITNESSES.

SECTION 1326. Subpoena defined, and who may issue.

1327. Form of subpoena.

1328. Subpoena, by whom and how served.

1329. Payment of the expenses of the witness when he is from without the county or is poor.

1330. Witness residing or served with subpoena out of the county, how compelled to attend,

1331. Disobedience to subpoena, etc.

1332. Failure to appear, undertaking forfeited.

1333. Temporary removal of imprisoned witness.

1326. The process by which the attendance of a witness before a court or magistrate is required is a subpoena; it may be signed and issued by:

1. A magistrate before whom a complaint is laid, for witnesses in the state, either on behalf of the people or of the defendant.

2. The district attorney, for witnesses in the state, in support of the prosecution, or for such other witnesses as the grand jury, upon an investigation pending before them, may direct.

3. The district attorney, for witnesses in the state, in support of an indictment or information, to appear before the court in which it is to be tried.

4. The clerk of the court in which an indictment or information is to be tried; and he must, at any time, upon application of the defendant, and without charge, issue as many blank subpœnas, subscribed by him as clerk, for witnesses in the state, as the defendant may require. [Amendment, approved April 9, 1880; in effect immediately.

1. Subpœna Defined.-Sec. 1985, C. C. P., post.

1327. A subpoena authorized by the last section must be substantially in the following form:

The People of the State of California to A. B.:

You are commanded to appear before C. D., a justice of the peace of township, in county (or as the case may be), at (naming the place), on (stating the day and hour), as a witness in a criminal action prosecuted by the people of the state of California against E. F.

Given under my hand this

day of

A. D. eighteen G. H., justice of the peace (or "J. K., district attorney," or By order of the court, L. M., clerk," or as the case may be). If books, papers, or documents are required, a direction to the following effect must be contained in the subpœna: "And you are required, also, to bring with you the following" (describing intelligibly the books, papers, or documents required).

1328. A subpoena may be served by any person, but a peace officer must serve in his county any subpoena delivered to him for service, either on the part of the people or of the defendant, and must, without delay, make a written return of the service, subscribed by him, stating the time and place of service. The service is made by showing the original to the witness personally and informing him of its contents.

1. Subpœna, How Served in Civil Cases.-Sec. 1987, C. C. P., post. 1329. When a person attends before a magistrate, grand jury, or court, as a witness in a criminal case, upon a subpoena, or in pursuance of an undertaking, and it appears that he has come from a place outside of the county, or that he is poor and unable to pay the expenses of such attendance, the court, at its discretion, if the attendance of the witness be upon a trial, by an order upon its minutes, or, in any other case, the judge, at his discretion, by a written order, may direct the county auditor to draw his warrant upon the county treasurer in favor of witness for a reasonable sum, to be specified in the order, for the necessary expenses of the witness. [Amendment, approved March 8, 1876; in effect sixtieth day after passage.

1330. No person is obliged to attend as a witness before a court or magistrate out of the county where the witness resides or is served with the subpoena, unless the judge of the court in which the offense is triable, or a justice of the supreme court, or a judge of a superior court, upon an affidavit of the district attorney or prosecutor, or of the defendant or his counsel, stating that he believes the evidence of the witness is material, and his attendance at the examination or trial necessary, shall indorse on the subpoena an order for the attendance of the wit