The testimony is entirely circumstantial. We have read it carefully and find nothing which directly connects the defendant with the homicide, assuming that one was committed. Where such are the conditions it is of vital importance to the defendant that the jury should be instructed fully and clearly upon the question of reasonable doubt; for the evidence must not only be consistent with the guilt of the defendant, but inconsistent with every other rational conclusion. (People v. Strong, 30 Cal. 154.) It is true that the Court, in a general way, at the request of the District Attorney, instructed the jury that they must be convinced of the guilt of the defendant beyond a reasonable doubt or acquit; but nothing was said as to what the law means by a rational doubt. The defendant, if he so desired, was entitled to a full and clear instruction upon that subject, both as to the fact of homicide and the participation of the defendant. His counsel prepared one which, so far as we can discover, is not only without any substantial objection, but is not even obnoxious to criticism. It seems to have been prepared with unusual care and precision. It was nevertheless refused. The Attorney-G-eneral concedes that it is sound and that it would have been better to have given it, but claims that the law upon the subject is sufficiently stated in the instructions which were given. We do not think so. We have held that it was not error to refuse to give an instruction, though unobjectionable in all respects, where the jury have been already instructed fully upon the point to which the instruction is directed ; but we have done so with reluctance, and we have repeatedly *436suggested that the Court in such cases ought to give the instruction and not take the chances of this Court looking at the matter in the same light. (People v. King, 27 Cal. 515 ; People v. Williams, ante, 280.) Suppose the result to be that the law is twice stated, it does no harm. No harm would be done if it was stated three times. On the contrary, it might in many cases result in good. What appears plain and easy of comprehension to bench and bar does not always appear so to those who occupy the jury box. Ife would be strange if it did. The better and safer course is for the Court never to refuse an instruction asked on behalf of a defendant in a criminal case, to which there is no valid objection, and District Attorneys ought never to object to such instructions. It is their duty to prosecute the case to the best of their ability, * but it is not their duty to oppose in any manner a full and fair defense. To do so is not to prosecute, but to persecute, and the latter is no part of their duty.
Judgment reversed and a new trial ordered.