A A Royal Mfg. Co. v. Board of Equal. of Taxes. The opinion of the court was delivered by 78 N. J. L. GUMMERE, CHIEF JUSTICE. This is a certiorari case brought to review an alleged excessive valuation of property for taxation, made in the year 1906, upon a manufacturing plant belonging to the Royal Manufacturing Company, and located in the city of Rahway. After the original valuation by the local assessor the property was revalued by the county board of taxation. That board raised the valuation of the buildings which constitute the plant from $12,000 to $16,800, leaving the valuation of the land (which was separately valued by the local assessor) undisturbed. The plaintiff in error then appealed from the county board's valuation to the state board of equalization of taxes, and that board, after hearing testimony, affirmed the value fixed upon the property by the county board. The certiorari was then sued out by the plaintiff in error for the purpose of reviewing the action of the state board. Before the Supreme Court it made two claimsfirst, that the value placed upon its property was relatively higher than that placed upon other property in Rahway, and second, that the value placed upon its property was in excess of its true value, and contended that for each of these reasons it was entitled to a material reduction in its assessment. The Supreme Court affirmed the action of the state board. We think it manifest that the Supreme Court rightly held that the first claim made by the prosecutor was without merit. The action of the taxing authorities in assessing other property in the same taxing district at less than its true value afforded no reason for reducing the assessment upon the prosecutor's property to less than its true value, for the constitution requires that property shall be assessed for taxation according to its true value, and a reduction below true value would be a violation of that constitutional provision. As to the second ground of complaint before the Supreme Court that court, after considering the testimony submitted, reached the conclusion that the property of the prosecutor was not assessed at more than its true value. This is a finding of fact which is not reviewable here, unless there is no evidence whatever to sustain it. Tuckerton Railroad Co. v. State Board of Assessors, 48 Vroom 614, and cases cited. That there was considerable evidence for this purpose is disclosed by an examination of the depositions returned with the writ. The judgment under review will be affirmed. For affirmance-THE CHIEF JUSTICE, GARRISON, SWAYZE, TRENCHARD, BERGEN, MINTURN, BOGERT, VREDENBURGH, VROOM, GRAY, DILL, JJ. 11. For reversal-None. THE STATE, DEFENDANT IN ERROR. v. GIOVANNI MAIONI, PLAINTIFF IN ERROR. Argued June 29, 1909-Decided November 15, 1909. 1. The opinion of a witness has no place in a judicial investigation unless he possesses, with regard to the particular subject of inquiry, a knowledge not acquired by ordinary persons. 2. Questions calling for the opinions of experts, upon mere abstract matters of science. not predicated upon, or related to the facts established by the proofs in the cause, are incompetent. 3. Under the system of criminal jurisprudence prevailing in this state the defence of insanity only goes to the question of the guilt or innocence of the accused. It does not operate to reduce the degree of guilt. 4. An instruction to the jury that an accused on trial for murder, who sets up insanity as a defence to the crime charged against him, must convince the jury by a preponderance of testimony that his mind was so deranged as to make him irresponsible for his act, does not require him to bear a burden greater than that which the law imposes upon him. The word "convince" in the connection in which it is used, is equivalent to "satisfy," and does not indicate that the defendant must prove his insanity by evidence which would produce absolute conviction in the minds of the jury. 5. An erroneous instruction to the jury upon a matter not involved in the issue being tried, and which could not have misled them or affected them in their determination of the questions before them for decision, affords no ground for a reversal. On error to Mercer Oyer and Terminer. State v. Maioni. For the plaintiff in error, Martin P. Devlin. 78 N. J. L. For the state, William J. Crossley, prosecutor of the pleas, and William R. Piper, assistant prosecutor of the pleas. The opinion of the court was delivered by GUMMERE, CHIEF JUSTICE. The defendant was indicted for the felonious killing of one Maria Lupo, by shooting her with a pistol, and was convicted of the crime of murder in the first degree. At the trial he sought to escape criminal responsibility principally upon the ground that he was an epileptic, and that when the homicide occurred he was suffering from an attack of the disease, and was totally unconscious of his act done at that time. In support of this line of defence Dr. Cotton was called to testify as an expert, and was asked by counsel for the defendant, among other questions, the following: "If a man be in a highly excited state-or, rather, an epileptic in a highly excited state-what is your opinion about his ability to have a deliberate intent to kill?” This question was overruled upon objection by the state, and its exclusion is made the basis of the first assignment of error. In our opinion the ruling complained of was correct. The witness had, just before this question was asked, testified that an epileptic, between attacks, might be perfectly clear mentally. The excluded question was not limited to the ability of a person to have a deliberate intent to kill during the period of an epileptic attack, or during a specified time before or after an attack. On the contrary, it was broad enough to cover the whole time between such attacks, and to call for the opinion of the expert as to whether an epileptic, at a time when he might be perfectly clear mentally, could, if he was in a highly excited state (even if that state was produced by a cause which would have brought about the same mental condition in an absolutely normal person), form a deliberate intent to kill. Whether a person whose mind is perfectly clear can form a deliberate intent to kill when he is laboring under a high degree of excitement produced by a perfectly natural cause, is a question upon which the opinion. of an alienist is of no more value than that of any other intelligent person, and the opinion of a witness has no place in a judicial investigation unless he possesses, with regard to the particular subject of inquiry, a knowledge not acquired by ordinary persons. But even if the witness could fairly be considered as an expert upon the subject inquired of, the question was, nevertheless, objectionable, for the matter with which it dealt was a mere abstraction. Questions calling for the opinions of experts upon matters of science must always be predicated upon, and relate to the facts established by the proofs in the case. Shoemaker v. Elmer, 41 Vroom 710. Professional opinions upon mere abstract questions of science tend to lead the minds of the jury away from the real points of inquiry and should always be excluded. 12 Am. & Eng. Encycl. L. (2d ed.) 424, and notes. The remaining assignments of error are directed at mistakes of law said to exist in the charge of the trial court to the jury. The first of these mistakes is said to have occurred in the instruction as to the scope of the defence of insanity. The charge upon that point was as follows: "The insanity of the defendant cannot be used for the purpose of reducing his crime from murder in the first degree to murder in the second degree. If responsible at all in this respect, he is responsible in the same degree as a sane man, and if he is not responsible at all, he is entitled to an acquittal in both degrees." In the case of Graves v. State, 16 Vroom 347, it was declared by this court that insanity is an affirmative defence; that the burden of proving it is upon the accused; that the law presumes, or assumes, that, at the time of committing the act for which he is tried, he was sane, and that, if he sets up insanity as a defence and fails to establish it, the presumption, or assumption, of sanity still stands. In the case of Mackin v. State, 30 Id. 495, we held that insanity is a defence to crime only when the diseased condition of mind was such that the defendant did not know the nature and quality of the act he was doing, or, if he did know it, that he did not know that what he was doing was wrong. Insanity being an affirmative defence, and that defence being made out only when the mental aberration is shown to be of the character defined in Mackin v. State, the failure by the defendant to prove the existence of such a mental condition at the time of committing the act charged against him, leaves the case before the jury in the same situation as if the defence had not been set up at all, that is, with the presumption existing that the defendant knew the nature and quality of the act he was doing and the wrongfulness of it. A person who has such knowledge stands upon the same plane, so far as accountability to the criminal law is concerned, as one who is entirely normal in his mental make-up. There was no error, therefore, in the instruction complained of. The defendant further challenges the correctness of the following instruction to the jury with relation to the burden. of proof upon the question of insanity: "Every man is presumed to be sane until the contrary is shown, and, therefore, the burden rests upon the defence to convince you by a preponderance of testimony that the mind of the defendant was deranged, and so deranged as to make him irresponsible for his act." The contention is that this instruction was erroneous because (to quote the language of his counsel) "when the court used the word 'convince' it called upon the defendant to conquer with testimony every doubt that might arise in the minds of the jurors." In the case of State v. Mangano, 48 Vroom 544, we held an instruction to the jury that when the defendant sets up intoxication as a partial excuse, "he must prove it by a preponderance of evidence, he must by the evidence create such a doubt as to his mental capacity as to convince you that he was unable to reason or deliberate," to be erroneous, the ground of our decision being that the use of the word "convince," in the connection in which it appeared, so leavened the general language of the instructions as to place upon the defendant a burden which the law did not require him to bear. In other words, that it nullified what preceded it, viz., the instruction that the burden upon the defendant was to prove intoxication by a preponderance of evidence, and substituted for it the instruction that he was required to prove it by evidence which would produce a |