At the trial Claude Miller, President of defendant corporation, was the principal witness for the defense. After extensive questioning about his training and experience, he was offered as an expert in the field of machine design. The trial judge twice made the following statement in the presence of the jury: “The court finds [Miller] is an expert in the field of machine design.” Plaintiff assigns this statement as reversible error in that it expressed the judge’s opinion as to the credibility of the witness. We agree with plaintiff.
In
Galloway v. Lawrence,
*415 “The ruling should have been put into the record in the absence of the jury for it was an expression of opinion by the court with reference to the professional qualifications of the defendant. It might well have affected the jury in reaching its decision that the child was not injured by the negligence of the defendant. There was no error in permitting the defendant to testify as an expert witness .... The court’s finding should not, however, have been stated in the presence of the jury.”
Id. The court held such an expression in the presence of the jury to be in violation of G.S. 1-180 (now G.S. 1A-1, Rule 51(a), N.C. Rules Civ. P.) which prohibits the trial judge from expressing an opinion on the weight to be given to particular evidence.
We believe the rationale in Galloway applies equally in the instant case. Just as in Galloway, the ultimate issue in the case sub judice is controlled by whether the defendant used requisite skill and care in performing a task. In Galloway the task was in the nature of medical treatment; in the instant case the task was in the area of machine design and manufacture; but in both cases
“comments by the able and learned trial judge ... dealt with the very questions which the jury was called upon to decide and were clearly prejudicial to the plaintiffs. The professional ability and skill of the defendant ... are questions for the jury, not for this Court or for the judge presiding at the trial.”
Id.
at 251,
Defendant asserts that Galloway is inapplicable to this case because Miller is not a party to the action. The record establishes the following:
(1) Miller was the president of the Miller Machine Company, Inc.
(2) Miller negotiated the contract with plaintiff Rann-bury-Kobee.
(3) Miller designed the machine according to plaintiffs specifications.
*416 (4) The actual work on the machine was supervised by Miller.
(5) Miller tested the machine.
(6) Miller told plaintiff of the cost overruns.
(7) Miller delivered the machine.
(8) Miller billed the plaintiff for the machine.
Further, Miller was never asked a hypothetical question or examined on any matter calling for an expert opinion, but testified only to things he had personally seen and heard in his dealings with plaintiff. The absence of a need to qualify Miller as an expert witness makes defendant’s motive questionable and aggravates the harm to plaintiff in having the principal opposition witness declared an expert machinist in the presence of the jury. Under these circumstances we find that the declaration of the court in the presence of the jury that Miller was an expert constituted an expression of opinion on the credibility of the witness in violation of G.S. 1A-1, Rule 51(a).
The foregoing reversible error requires a new trial but discussion of plaintiffs argument that the trial court erred in refusing to admit evidence tending to show plaintiff’s loss of business profits may be beneficial upon retrial. We find no error on the record before us; however, the ruling of the trial court would not be controlling on retrial if the plaintiff offers evidence of lost profits which meet the required standard of reliability.
Lost profits are a legitimate element of damages for breach of contract.
“ ‘If a regular and established business is wrongfully interrupted, damage thereto can be shown by proving the usual profits for a reasonable time anterior to the wrong complained of.’ ”
Steffan v. Meiselman,
*417
Plaintiff may base its claim for lost profits upon other factors, but these factors must be equally as reliable as a proven record of profits and may not involve conjecture or speculation.
Id.
at 159,
We do agree with the trial judge that the foregoing evidence failed to make out with sufficient certainty the plaintiffs loss of profits due to the delay in its commencement of operations.
Other assignments of error are not discussed since they are not likely to recur upon retrial.
Reversed and Remanded.
