The opinion of the court was delivered by

Where circumstantial evidencealone is relied upon for a conviction, proof of a motive upon the part of the accused which would induce him to commit the crime is always competent, and, if a strong motive be shown, *533 unquestionably it would require a less amount of other evidence to bring about a conviction. In other words, motive to commit crime, if shown, may in many cases be sufficient alone, almost, to induce a belief of guilt. Upon the other hand, where no motive for the commission of a crime can be shown, it is almost impossible to convince the mind of guilt. Men do not ordinarily commit grave crimes unless there is, in their minds, a motive strong enough to overcome the natural repugnance against crime and the fear of punishment which usually follows detection. This view of this question is so universally recognized as being true, that it has become incorporated into the law, and in almost all cases where the guilt of a defendant depends upon the facts and circumstances in proof in the case, the court instructs the jury to consider the motive or lack of motive which the proof shows may or may not exist in the mind of a defendant on trial charged with crime. Such being the law, it was right and proper for the court, in the trial of this case, to permit the territory to establish, upon the part of this defendant and those associated with him, a motive for the killing of Hoffman, and if it could have been shown that Hoffman was engaged in the attempt to fasten the responsibility for express robbery upon them, it was proper to permit the proof, if, as the court well said, the knowledge of what Hoffman was doing was brought home to the parties charged with the killing. But we think when the prosecution closed its case without supplying such proof, either by the direct testimony of witnesses or by proof of facts or circumstances from which the jury might reasonably infer that the defendant had such a knowledge, prejudicial error was committed against the defendant. The only prdper office which the proof of Hoffman’s efforts *534 against tlie defendant and his associates could fill, was for the purpose of showing a motive upon their part, strong enough to tempt them to the murder of Hoffman. This was the view which the trial court took, as indicated by the statement that “unless the' knowledge that he, Hoffman, was working for- that purpose was brought home to the defendant or some persons working with him, it was not competent.” The evidence in this case does not meet this requirement because it does not appear that the defendant or those with whom he associated knew what Hoffman was engaged in; neither does it appear that any attempt was made to bring such knowledge home to such parties. A motive cannot operate to influence, until the facts which create the motive exist. The facts upon which a motive is based cannot operate upon-the mind until they are known by the party against whom the motive is assigned. If one person should contemplate and undertake a great wrong against another, such a wrong as would induce in the mind of the person against whom it was directed a motive to kill, and yet such contemplated wrong was unknown to the party, it cannot be justly said that a motive to kill could exist, because the party wronged had no knowledge of the facts which would be necessary to create the motive. Applying this reasoning to the case under consideration, it does not appear that the defendant, or any of the persons jointly indicted with him, knew that Hoffman was trying to implicate him or any of their friends in the express robberies; upon the other hand, it does appear by the testimony of at least one witness that such fact was not generally known. In the absence of proof of knowledge upon the part of the defendant, the evidence was improper to show a motive to kill. It could not have been offered or received for any other purpose. We *535 cannot tell how much weight the jury may have attached to such testimony; they may have given, it great consideration, and upon the other hand they may have thought the testimony sufficient without the showing of the motive. About this we have no information. We do know that the evidence was before the jury and that it may have prejudiced the defendant. The supreme court of Kansas in State v. Reed, 53 Kan. 767; 37 Pac. 174, in a case where a motive for murder was sought to be shown by the proof of facts not brought to the knowledge of the defendant, the court by Johnston, J., said:

“A more serious objection is made to interviews and conversations held with the deceased some time prior to the shooting when the defendant was not present and of which he had no knowledge. A witness was permitted to detail at length a meeting between himself and Hacker on the day before the shooting, the taking of a night drive with the deceased during which he related to the witness his troubles at Wellington, and his plans for leaving that place and going to Missouri. He was allowed to testify what the mood and manner of the deceased were on that day, and to relate the reasons given by the deceased for leaving Wellington. The reasons stated was the interference in his family and the trouble made by the defendant. Another witness, over objection, related that he had met the deceased on the next day and had a conversation with him, in the absence of the defendant, in which the deceased informed him, among other things, that he had determined to go to Missouri, and the reason given was ‘that if he could get his wife away from where Judge Keed was they could get along all right together.’ Acts and conduct of the deceased previous to the fatal encounter which formed a part of the res gestas or which tended to throw light upon the question of motive or malice might be admitted in evidence, but the acts or conduct of deceased which are not a part of the ves gestas and which could not have *536 influenced tlie defendant in the commission of the homicide cannot be shown. The manner and conduct of deceased on the day previous to the killing were not known to the defendant and are not connected with the homicide, and therefore the defendant could not be affected thereby. Anything that would throw light on the homicide and anything that would operate upon the mind of the defendant can be shown; but evidence of the acts or manner of the deceased which never came to the knowledge of the defendant could not be proved.”

We think this view of the law eminently correct. In support thereof we cite the following cases, which bear upon this proposition: People v. Corkhuff, 24 Cal. 640; Commonwealth v. Gray, [Ky.], 30 S. W. Rep. 1015; People v. Tress, [Cal.], 40 Pac. 752; Montag v. People [Ill.], 30 S. E. Rep. 237; State v. Punshon, [Mo.], 27 S. W. Rep. 1111; Cheek v. State, 35 Ind. 492; Combs v. State, 75 Ind. 215; Graves v. The People, [Cal.], 32 Pac. 63.

It is unnecessary to consider the other errors assigned. For the reasons stated, the judgment of the lower court is vacated and the cause remanded for a new trial.