This was an action brought in the district court of Salt Lake County to recover damages for personal injuries alleged to have been sustained by the plaintiff while in the employ of the defendant as a railroad brakeman. In substance, the complaint alleges that on the 11th day of March, 1915, while the plaintiff was in the employ of the defendant as a rear brakeman on an inter-state freight train, he was directed at Thistle, Utah, by the conductor in charge of said train, to assist in switching a certain car from the defendant’s main line to a side track, and while acting in obedience to said order was jerked off the car on which he was required to go, and was injured by reason of the careless and negligent manner in which an incompetent engineer operated the engine and train. The answer denies negligence, and affirmatively alleges that the regular engineer placed in charge of the engine left it to go to an eating house for his meal, and in his absence the conductor of the train, without right or authority, and without instructions from the defendant, proceeded to take charge of the engine and operate it in doing the switching at the time and place plaintiff was injured; that although the conductor was competent to handle the engine, and did handle it competently and carefully, his acts in so doing were contrary to defendant’s instructions and wholly outside the scope and course of his employment. Trial was to a jury resulting in a verdict and judgment for the plaintiff. Defendant appeals.
The numerous errors assigned on appeal are directed to the rulings of the trial court in admitting and excluding evidence, in denying defendant’s motion for a nonsuit and for a directed verdict, and the giving of certain instructions to the jury.
The facts, in brief, as disclosed by the testimony, are that the plaintiff was, at the time of the accident of which he complains, an experienced railroad brakeman in the employ of the defendant engaged in the duties of a rear brakeman on a *441freight train engaged in interstate commerce. The train crew consisted of the plaintiff, as rear brakeman, a head brakeman, conductor, fireman, and an engineer. The train, consisting of about seventy-five cars, was being moved westward from Helper to Salt Lake City. The train arrived at Thistle at about nine o’clock a. m. Before arriving at Thistle, the conductor had received orders to set a car out of the train at that station and leave it upon a siding for transportation over another branch of defendant’s railroad. The conductor communicated his orders to the brakeman. Immediately on the arrival of the train at Thistle, the engineer and fireman proceeded to vacate the engine and go to a nearby eating house for their breakfast. Meanwhile, in the absence of the engineer and fireman, without the knowledge of the plaintiff, the conductor mounted the engine and began operating it in the cutting out of the ear to be left at Thistle, and switching it from the defendant’s main line to -the side track where it was to be left. The testimony further shows that the signals given in this switching process were first given by the conductor in charge of the engine to the head brakeman, and by him communicated to the rear brakeman, the plaintiff, who was not in a position to see the conductor on the engine. In the movement of the train of cars by the engine a violent backward jerk of the car occurred on which the plaintiff was required to go in order to do his work, causing him to break his hold upon the ladder at the side and fall to the track, where the wheels ran over his leg and inflicted the injuries of which he complains. There is very little conflict in the evidence, except as to whether or not the engine was negligently handled by the conductor. There is substantial evidence in the record that tends to show the conductor was negligent in that regard.
The principal errors assigned by defendant on appeal go to the question whether or not, as a matter of law, the defendant is liable to the plaintiff for the injuries he sustained while the conductor was thus operating the engine in the absence of the engineer.
It must be conceded from the testimony given in this case that, both in actual practice and under the rules of the de*442fendant company, the only person who could rightfully operate the engine was the engineer. Rule 443 of the defendant company provides:
“While switching, engineer and fireman must remain on the engine and must exercise great care in handling the engine while yardmen or trainmen are making couplings, and also give close attention to signals. ’ ’ 1
The engineer testified:
“Under the company’s instructions and rules and regulations, at that time it was my duty to operate the engine, and nobody’s else.”
The plaintiff himself testified:
“I know that the conductor had no right to run the engine. I know that Conductor Clifford, on that occasion, had no right to operate that engine. ’ ’
The conductor testified:
“I had no excuse at all for operating the engine; none whatever. It was a responsibility I assumed myself. It was an utter disregard of the orders of the company, without any reason whatever.”
It is therefore contended by the defendant that the conductor of the train was operating the engine at the time of the accident in question without any authority from the defendant and beyond the scope and the duties of the 1, 2 employment.
It becomes important, in view of the foregoing testimony and the contention made by the defendant, that we take into consideration the effect of certain other rules offered in evidence bearing upon the functions of the conductor and the scope of his duties while in charge of defendant’s train. They provide:
Rule 334 (with respect to freight conductors). “They will be held responsible for the conduct of all persons employed on their trains, and must report any misconduct or neglect of duty.”
Rule 315. “Station work should be done immediately on arrival. ’ ’
*443Rule 317. “Conductors will eomply with instructions of agents in placing cars and doing other station work. If necessary to move cars for loading or unloading, they must be replaced.”
Rule 204. “Train orders must be addressed to those who are to execute them, naming the place at which each is to receive a copy. Those for a train must be addressed to the conductor and engineer, and also to any one who acts as its pilot. A copy for each person addressed must be supplied by the operator. Orders addressed to operators respecting the movements of trains must be respected by conductors and engineers the same as if addressed to them. ’ ’
The trial court, in the face of the foregoing uncontradicted testimony, denied defendant’s motion for a nonsuit and also a motion for a directed verdict in defendant’s favor, and proceeded at the conclusion of the testimony to instruct the jury as follows:
‘1 The court instructs you as a matter of law that under the undisputed evidence in this case the conductor stood in such relation to the train and the engine that his acts must be deemed to be the acts of the defendant company. In handling the engine himself he was violating his duty to the company, but his act was nevertheless the act of the company. You are therefore instructed that, if you find from a preponderance of the evidence that the plaintiff’s injuries were caused by the negligence of the conductor in the manner of his stopping the train at the time of the accident, the defendant company must answer in damages to the plaintiff, notwithstanding the fact it had forbidden its conductors to operate its engine.”
Under the facts and circumstances disclosed by the record on this appeal, we are of the opinion that the rulings of the trial court in denying defendant’s motion for a nonsuit and for a directed verdict, and the giving of the foregoing instruction to the jury, over the defendant’s objection, are to be sustained, both on principle and authority.
While the testimony shows that the act of the conductor in operating the defendant’s engine was in disobedience of the *444instructions and rules of the defendant company, yet it appears that the nature of his employment was such that at all times it became his duty as a representative of the defendant to answer "for the conduct of all persons employed on the train”; that, while under the defendant’s rules it was the duty of the engineer and fireman to remain upon the engine when the train erew was engaged in switching cars, the train was to be run under the directions of the conductor. The defendant’s rules required the conductor to see to it that "station work was done immediately on arrival” of the train, and ‘ ‘ conductors will comply with instructions of agents in placing cars and doing other station work,” and in doing so he is to be held responsible for the safety of the train.
It would be difficult to conceive of circumstances under which the master could more justly be held to answer for the negligent act of the employee than in the case at bar. The acts of the plaintiff and every other member of the train crew were under the direct supervision of the defendant’s conductor. He directed them in all their work and in the full performance of their duties. He was expressly charged, under the instructions and rules of the defendant, with the safety of the train and in seeing that its movement was so directed as to afford safety for defendant’s employees while engaged in their work upon it. As to the plaintiff in that particular he failed. From the very necessity of things his wrongful and incompetent acts in that regard must relate back and be attributable to the defendant. The plain duty of the defendant in sending out a train of cars to properly safeguard the persons and lives of its employees working upon it cannot be questioned. The responsibility must rest somewhere. That it may not be shifted from the defendant company to its chosen conductor, who is given full control and directs every movement of the train, because he disregards or violates the instructions given him and wrongfully does himself what he is empowered to direct others to do, to our minds is equally plain.
Counsel for defendant contend that as a matter of law the conductor’s acts in operating the engine were not "within the *445scope of Ms employment,” and in support of that contention have cited and quoted copiously in their brief and argument from the following cases and authorities, to-wit: 3 Herbert v. Fox, 1 L. R. App. Cas. 405; Roe v. Burkenhead, L. & C. J. R. Co., 7 Exch. 36; Washington Gaslight Co. v. Landsden, 172 U. S. 534, 19 Sup. Ct. 296, 43 L. Ed. 543; Spokane & Inland Empire R. Co. v. Campbell, 241 U. S. 497, 36 Sup. Ct. 683, 60 L. Ed. 1125; Lake Shore, etc. Ry. Co. v. Prentice, 147 U. S. 101, 109, 13 Sup. Ct. 261, 37 L. Ed. 97; Byrne v. Londonderry Tramway Co., 2 I. R. 457; Fredericks v. Chicago & N. W. R. Co., 96 Neb. 27, 146 N. W. 1011, L. R. A. 1916F, 869; McKenzie v. McLeod, 10 Bing. 385; Mitchell v. Craswell, 13 Com. Bench, 237; Pittsburg, C., C. & St. L. Ry. Co. v. Adams, 25 Ind. App. 164, 56 N. E. 101; Walker v. Hannibal & St. J. R. Co., 121 Mo. 575, 26 S. W. 360, 24 L. R. A. 363, 12 Am. St. Rep. 547; 6 Labatt, M. & S. (2d Ed.) section 2285; Philadelphia & R. R. R. Co. v. Derby, 14 How. 468, 14 L. Ed. 502; Limpus v. London Omnibus Co., 1 H. & C. 526, 130 Rev. Rep. 641; New York Central, etc., R. R. Co. v. United States, 212 U. S. 481-483, 29 Sup. Ct. 304, 53 L. Ed. 613; Baltimore & O. R. Co. v. Doty, 133 Fed. 866, 67 C. C. A. 38; International Text-Book Co. v. Heartt, 136 Fed. 129, 69 C. C. A. 127; Healy v. Patterson, 123 Iowa, 73, 98 N. W. 576; Western Real Estate Trustees v. Hughes, 172 Fed. 206, 96 C. C. A. 658; Aldrich v. Boston & W. R. R. Co., 100 Mass. 31, 1 Am. Rep. 76, 97 Am. Dec. 74; Fitzgerald v. Fitzgerald, etc., Cons. Co., 44 Neb. 463, 62 N. W. 899-904; Goodloe v. Memphis & C. R. Co., 107 Ala. 233, 18 South. 166, 29 L. R. A. 729, 730, 54 Am. St. Rep. 67; Rounds v. D., L. & W. Ry., 64 N. Y. 129, 21 Am. Rep. 597; Core v. Ohio River R. Co., 38 W. Va. 456, 18 S. E. 596; Mickelson v. Railway Co., 23 Utah, 42, 64 Pac. 463.
We have examined these eases and authorities with more than ordinary care, and they but tend to show the manifold application of the words “within the scope of his employment ’ ’ to given statements of facts and circumstances, without demonstrating that the words are susceptible of being so defined that they may be held to be of general application. In *446other words, when fully considered, they demonstrate nothing more than the difficulty the courts have in the application of the phrase, particularly in eases involving the liability of a master for the negligent or wrongful acts of his servant. Their perusal convinces that the question as to whether or not a servant is acting “within the scope of his employment” at the time of the commission of a wrongful or negligent act causing an injury to a third party must be determined from the facts and circumstances of the particular case under consideration.
For the reasons heretofore assigned, we think the case at bar can be very readily distinguished from the many eases cited by counsel for defendant in their brief and argument. Time, the defendant’s conductor was not acting under any express authority, and his acts in operating the engine were irregular and in violation of the defendant’s rules; but, nevertheless, the very duties he was called upon to perform, in directing and controlling the train and its crew while in the service of the defendant, were such that when he wrongfully undertook to operate the engine in the absence of the engineer, and the plaintiff was thereby injured by reason of his careless and negligent acts, he was still acting in the performance of the defendant’s service and was within the scope of his employment. Conchin v. El Paso & S. W. R. Co., 13 Ariz. 259, 108 Pac. 260, 28 L. R. A. (N. S.) 88; Jones v. Weigand, 134 App. Div. 644, 119 N. Y. Supp. 441.
It is also contended that the trial court erred in charging the jury as to the burden of proof of contributory negligence.
The instruction complained of as given by the court was as follows:
“In this case the defendant pleads that the plaintiff at the time of receiving his injuries was guilty of negligence that contributed to his own injury. On this 4 issue the court instructs you that the burden of proof is on the defendant; and if upon this issue the preponderance of the evidence is in favor of the plaintiff, or if it is *447equally balanced., you should find such issue in favor of the plaintiff.”
Standing alone, the instruction, as given, would be clearly erroneous, in that it thus restricts the proof as to contributory negligence to the defendant’s testimony alone, and deprives the defendant of the benefit of plaintiff’s testimony in that regard.
The rule bearing on this question was announced by Mr. Justice Frick, speaking for this court in the ease of Conway v. Salt Lake & O. Ry. Co., 47 Utah, 510, 5 155 Pac. 339, L. R. A. 1916D, 1109, wherein it was said :
‘1 The true rule in this jurisdiction is that when the evidence is conflicting, or when different inferences may he drawn therefrom, the burden of establishing contributory negligence is upon the defendant, regardless of whether the evidence with regard thereto comes from the plaintiff’s or the defendant’s witnesses, and in either event contributory negligence must be established by a preponderance of the evidence given upon that ■subject.”
However, in the case at bar, the court told the jury by a subsequent instruction that they “should consider all of the evidence together and should not pick out any particular statement of any witness and give it undue weight.” Moreover, the record here fails to disclose any testimony given in behalf of the plaintiff tending to show that the plaintiff was guilty of contributory negligence, and therefore the giving of the instruction complained of cannot be held to be prejudicial error. .
It is further contended by the defendant that the trial court erred in refusing to permit a physician, who had attended the plaintiff for his injuries, to testify. On direct examination the plaintiff himself had testified somewhat in detail concerning the character and extent of his injuries, the pain and suffering endured, and his physical condition before and since the accident. The plaintiff had also testified concerning the mode of treatment of his injuries and their character as described to him by the physician, 6, 7 Dr. John F. Critchlow, whose competency to testify was challenged by the plaintiff under the provisions of *448subdivision 4, section 3414, Comp. Laws 1907, as amended by chapter 109, Laws Utah 1911, which provide:
“A physician or surgeon cannot, without the consent of his patient, be examined in a civil action, as to any information acquired in attending the patient which was necessary to enable him to prescribe or act for the patient.”
Defendant contends that the plaintiff’s right to invoke the provisions of the foregoing statute was waived when the plaintiff himself testified concerning his physical condition before and after the accident, the character and extent of his injuries, and the mode of treatment, and also by reason of the plaintiff having produced as a witness, in his own behalf, Dr. H. S. Scott, a physician who had also attended and examined him, who testified in great detail concerning the character and extent of the injuries received by plaintiff in the accident, and. the actual and probable results as affecting his future ability to perform manual labor, before the defendant produced Dr. Critehlow as a witness in its behalf and propounded to him the following questions:
‘ ‘ Q. Now, what did you ascertain from your first examination of Mr. Dahlquist’s leg ?
”Q. State the condition of the bones, as you saw them.
“Q. On various occasions — don’t state what you saw — just answer yes or no, whether or not on various occasions you made an examination of his leg in treating it, and saw what the conditions of the bones were? A. Yes, sir.
”Q. And the union after some considerable time after the accident?
“Q. You did see the bone itself, Doctor, some considerable time after you had the case in charge, from time to time?
‘‘Q. Prom'what you saw of the condition of the bone, Doctor, I wish you would state whether there was any condition there which indicated to you the possibility or probability of the presence of syphilis.
‘ ‘ Q.. Did you, yourself, treat the plaintiff for syphilis ?
“Q. Did you inform the plaintiff at any time that he was being treated for syphilis ? ’ ’
*449In view of the record here, we think the ruling of the trial court in refusing to permit the witness Dr. Critchlow to make answer to the foregoing questions was not only erroneous, but clearly prejudicial to the defendant’s right to a fair and impartial trial of the issues involved in this action. When the witness Dr. Critchlow was offered by the defendant and the foregoing questions propounded to him, the plaintiff had not only, as we have heretofore pointed out, voluntarily permitted one of his physicians to testify at great length concerning the character and extent of the injuries complained of, but also as to their permanency and the effect they would have in after years, and the causes therefor, and as to the conclusions he had reached why they were not occasioned by the syphilitic condition of the plaintiff. The plaintiff had also testified in his own behalf that:
“The doctor found that gristle had grown in between the bones, and told me that I had a fibrous union. * * * My leg is bent out a little bit now, and if I were to use any more pressure on it, as Dr. Critchlow said, I might get a bigger bow. ’ ’
We cannot conceive of a case wherein the very purpose of the statute, as declared in the language of the statute itself (section 3414) that “there are particular relations in which it is the policy of the law to encourage confidence and to preserve it inviolate, ’ ’ could be more clearly waived than in the case at bar, when the plaintiff by himself and one of his examining physicians voluntarily disclosed by their testimony (obviously for the purpose of enhancing the amount of his claim for damages against the defendant) all the statute was designed to preserve to the plaintiff as inviolate.
While there are some cases to the contrary, we think the great weight of authority sustains our view that in the case at bar the plaintiff waived his privilege under the statute, and that the trial court erred in refusing to permit the defendant’s witness Dr. Critchlow to testify. Wigmore, Evidence, sections 2388-2390; Chamberlayne, Mod. Law of Evid. section 3705a; 40 Cyc. pp. 2399, 2400; City of Tulsa v. Wicker, 42 Okl. 539, 141 Pac. 963; McKinney v. Grand Street R. Co., 104 N. Y. 352, 10 N. E. 544; Webb v. Met. St. Ry. Co., 89 Mo. App. *450604; Lane v. Boicourt, 128 Ind. 420, 27 N. E. 1111, 25 Am. St. Rep. 442; Treanor v. Manhattan Ry. Co., 16 N. Y. Supp. 536; Epstein v. Pennsylvania R. Co., 250 Mo. 1, 156 S. W. 699, 48 L. R. A, (N. S.) 394, Ann. Cas. 1915A, 423.
Doubtless it was the purpose of the defendant in producing Dr. Critehlow as a witness to show by his testimony the falsity of, or to at least qualify, the statements made by the plaintiff and the witness Dr. Scott concerning plaintiff’s injuries, their treatment, and plaintiff’s then physical condition, resulting therefrom. The right to do so, tested by every principle of justice, in our judgment, should have been accorded it by the trial court.
It is therefore ordered that the judgment of the district court be, and it is, reversed, and the cause is remanded to said court with directions to grant a new trial and to proceed in accordance with the views herein expressed. Defendant to recover costs.