take the judgment of unskilled jurors than the opinions of hired and generally biased experts."
Now, this rule has been repeatedly recognized and followed by the courts in this state. In the case of Wilcox vs. State, 94. Tenn., at 112, your own supreme court speaking in regard to this subject, held that it was no error to charge the jury as follows:
Expert Testimony Field of Speculation
"While expert testimony is sometimes the only means of, or the best way to reach the truth, yet it is largely a field of speculation besought with pitfalls and uncertainties, and requires patient and intelligent investigation to reach the truth."
The same rule is stated and followed in Persons vs. State, 6 Pickle, 291, and Adkins vs. State, 119 Tenn., at 458. The following quotations, if the court please, on this point, are taken from corpus juris, Volume 22, page 498, and following, and are merely the expressions of opinions that have received such widespread recognition and have been followed and cited until they have become axioms of the law.
Experts Endanger Case.
"The danger involved in receiving the opinion of the witness is that the jury may substitute such an opinion for their own. But courts will not require the parties to encounter this danger unless necessity therefore appears. The jury should not be influenced by the opinion of anyone who is not any more competent to form one than they themselves are. The verdict should express the jurors' own independent conclusions from the facts and circumstances in evidence, and not be the echo of witnesses, perhaps not unbiased."
Of course, if the court please, I do not mean to argue that there are not cases where it is absolutely necessary to have opinions of experts, where the matters in issue are of such a technical or involved nature that expert opinion is the only way by which the truth as to facts may be arrived at. These exceptions will, no doubt, be fully argued to you by the counsel for the defense. However, that may be, the courts are unanimous in adhering to the rule that expert testimony can be introduced only under the stress of necessity. In other words, the court will seek the aid of opinion evidence only where the issues involved or facts are of such a complex nature that the man of ordinary understanding is not competent or qualified to form an opinion, but, if the court please, even this exception is limited by the rule of law to which I shall refer later in my argument, that prohibits in any event the introduction of expert testimony upon the very facts that the jury are to pass upon.
The first test that the court should apply to determine whether expert testimony is admissible in any event, is, whether the facts relevant to the issues are such that they can be introduced into evidence, and whether the jury are competent to draw a reasonable inference therefrom—not necessarily the inference that the court would draw, or that I would draw, or that the expert would draw; and are they competent to draw a reasonable inference of their own. It is the rule supported by the weight of authority, I think, in almost ever state of this Union that where all relevant facts can be introduced in evidence and the jury are competent to draw their reasonable inferences, therefrom, that opinion evidence may not be received. This is the law in the state of Tennessee.
In the case of Cumberland Telephone and Telegraph company vs. Dooley, 110 Tenn., page 109, it was sought to introduce the opinion of a witness as to whether or not a fire could have been stopped and controlled with the apparatus then and there at hand; and, it was held that such evidence was not properly a subject of expert opinion, inasmuch as every fact constituting an element of the opinion of such witnesses was capable of being presented to the jury.
