(dissenting, with whom Lynch, J., joins). “ ‘Negligence, without qualification and in its ordinary sense, is the failure of a responsible person, either by omission or by action, to exercise that degree of care, vigilance and fore*142thought which, in the discharge of the duty then resting on him, the person of ordinary caution and prudence ought to exercise under the particular circumstances. It is a want of diligence commensurate with the requirement of the duty at the moment imposed by the law.’ Altman v. Aronson, 231 Mass. 588, 591 (1919). Ordinarily, where a duty of care is established by law, the standard by which a party’s performance is measured is the conduct expected of an ordinarily prudent person in similar circumstances. The standard is not established by the most prudent person conceivable, nor by the least prudent, but by the person who is thought to be ordinarily prudent. . . . The same standard is frequently expressed in terms of ‘reasonable care,’. . .” (citations omitted). Toubiana v. Priestly, 402 Mass. 84, 88 (1988).
“In determining whether the law ought to provide that a duty of care is owed by one person to another, we look to existing social values and customs, and to appropriate social policy. Schofield v. Merrill, 386 Mass. 244, 246-254 (1982). A basic principle of negligence law is that ordinarily everyone has a duty to refrain from affirmative acts that unreasonably expose others to a risk of harm. Thus, we have held that a keeper of a tavern owes to travelers on the highway a duty of care with respect to the furnishing of alcoholic beverages to his customers, Cimino v. Milford Keg, Inc., 385 Mass. 323, 327 (1982); Adamian v. Three Sons, Inc., 353 Mass. 498 (1968), and the proprietor of a liquor store owes a duty of care to the public which may be violated by selling liquor to minors, Michnik-Zilberman v. Gordon’s Liquor, Inc., 390 Mass. 6, 10-12 (1983).” Yakubowicz v. Paramount Pictures Corp., 404 Mass. 624, 629-630 (1989).
I agree with the court that the Norwood Country Club owed the deceased minor, who was a guest at the club, a duty to refrain from conduct that would unreasonably expose her to a risk of harm, including a risk of bodily injury or death, as a consequence of her consumption of alcoholic beverages provided by the club. Thus, if there had been evidence that, in violation of G. L. c. 138, § 34, a club employee sold or delivered alcoholic beverages to the deceased minor the jury would have been warranted in finding negligence. However, there was no such evidence in this case. Indeed, there was no evidence that any club employee knew that minors were obtaining alcoholic drinks from any source. The question in *143this case, then, is whether, on any reasonable view of the evidence most favorable to the plaintiffs, the jury would have been warranted in finding that the club’s employees’ failure to make a timely discovery of the deceased minor’s consumption of alcoholic beverages and to prevent its continuation and therefore the tragedy that ensued was due to the employees’ lack of ordinary prudence. I would answer that question, “No.” I would affirm the judgment for the defendant.
In reaching the opposite conclusion, the court states that the employees knew there were teenagers at the party, that over the course of the evening (five hours plus) the deceased minor and five other teenagers “drank more than forty glasses of a pinkish liquid [which] might have been fruit juice,” and that “it is a reasonable inference . . . that an experienced observer might have supposed that some of these were ‘sea breezes,’ a concoction specifically obtained by the minors to look like something less potent.” Ante at 139. The court also says that “[t]here was testimony that, from the behavior of some of the teenagers, an experienced observer might have inferred that they had been drinking, and drinking more than a little.” Ante at 139. In a footnote, ante at 140 n.10, the court states, “Moran testified that he observed plastic cups with pinkish liquid in them on the table at which the minors sat during the course of the evening. The jury could have disbelieved his statement that he never observed minors drinking what he knew to be sea breezes.”
“In violation of club policies,” the court states, “Erwin sold multiple drinks on numerous occasions, and on at least three occasions permitted a minor to carry drinks from the bar. The record also indicates that on another occasion, the club had set up a bar in the function room so that the bartender could monitor the guests; on this night they decided not to. On other nights, the bartender walks through the function room; on this night only Moran entered the room. Finally, in violation of club rules, Moran drank at least three alcoholic drinks while on duty.” Ante at 140. In a footnote, the court cites testimony that “the bartender’s responsibility is, whenever he or she has a chance, to stroll through the party and make sure everything is being done according to the club’s policies. That the bartender failed to make this chance knowing that minors were present could have been considered negligent behavior by the jury. There was also *144testimony that it was the common policy and procedure of the club to make special arrangements for the supervision of minors to make sure that they would not be served alcoholic beverages. The club’s assignment to Moran of this task when it was his family members that he was to supervise could have been considered negligent by the jury.” Ante at 140 n.12.
In summation, the court observes that “the record offers sufficient facts to have allowed a jury to conclude that the defendant, through its agent Moran, knew or should have known — certainly long before the party came to an end and the several drunken teenagers were leaving — that there had been considerable underage drinking.” Apparently relying exclusively, or at least primarily, on Moran’s failure “to head off the tragedy that eventually — and foreseeably — occurred” and on his failure to “enlist [ ] the adults present to monitor the teenagers’ departure,” the court concludes that the judgment notwithstanding the verdict should be vacated and the jury verdict reinstated. Ante at 141.
Before discussing the court’s rationale, it is important that the record be set straight regarding the contents of the evidentiary record: (1) The court’s statement that there was evidence that on at least three occasions the bartender permitted a minor to carry drinks from the bar may suggest that on the strength of that testimony the jury would have been warranted in finding that on those occasions the bartender sold or served alcoholic drinks to a minor or minors. However, the court’s statement of the testimony is incomplete. Earlier in its opinion the court more fully and more accurately states: “A minor . . . testified that, on at least three occasions, he aided two adults by carrying multiple drinks . . . from the bar.” Clearly, the jury would not have been warranted by that evidence, or any other, in finding that the bartender sold or served drinks to a minor. (2) The court writes, “The record also indicates that on another occasion, the club had set up a bar in the function room so that the bartender could monitor the guests; on this night they decided not to.” Ante at 140. I agree that there was evidence that, on one prior occasion, the club set up a bar in the function room. There was not a shred of evidence, however, concerning why that was done. Specifically, there was no evidence that it was done on that occasion to enable the bartender to monitor the guests. *145Most importantly, there was no evidence that it was done because the club “was generally aware of the risks inherent in the sale of alcoholic beverages and believed itself under a duty to minimize them.” Ante at 141.
The court appears to conclude that, standing alone, the bartender’s failure to “make the chance” to stroll “through the party” and monitor it, and the club’s assignment of Moran to supervise the minors “when it was his family members that he was to supervise” would warrant findings of negligence. The court offers no explanation — understandably — because a finding of negligence or causation would not have been warranted by that evidence.
The court, of course, does not limit its discussion to the evidence discussed in the preceding paragraph. The court appears to reason also that the jury would have been warranted in concluding that an ordinarily prudent commercial host of a large party similar to the party involved here (a wedding reception, for example) would recognize and then fulfil an obligation not only to refrain from selling or serving alcohol to minor guests or to respond to known alcohol consumption by minors, but also to police the party with a view to detecting whether minors are obtaining alcoholic drinks from adult relatives or friends. The court does not discuss how in this case the ordinarily prudent monitor would have made this discovery since it was not visually apparent from the glasses used by the minors. The court simply implies without explanation that the jury would have been warranted in concluding that ordinary prudence required something more than visual inspection — interrogation of the guests, perhaps (which might or might not have been successful) — or perhaps Moran’s sipping from the minors’ glasses and, upon discovering alcohol, taking action, the nature of which the court leaves undefined. I simply do not agree with the court’s statement that “the record offers sufficient facts to have allowed a jury to conclude that the defendant, through its agent Moran, knew[1] or should have known — certainly long before the party came to an end and the several drunken teenagers *146were leaving — that there had been considerable underage drinking.” Ante at 141. Surely, the testimony of the deceased’s date, who had participated with the deceased and others in the consumption of camouflaged alcoholic drinks, that “the decedent seemed [to him] intoxicated towards the end of the party,” and the testimony of another teenager that other teenagers appeared to him to be somewhat intoxicated, would not have warranted the jury in concluding that “[a]t an earlier point in the evening the underage drinking should have been [discovered and] shut down” by Moran.2 Ante at 141.
I conclude this separate opinion with one last observation. Hopefully, the court’s decision to reinstate the jury verdict for the plaintiffs does not depend on the sufficiency of the evidence to warrant the jury in finding that Moran was negligent because, “[b]y the end of the evening, [he] might have enlisted the adults present to monitor the teenagers’ departure” and he negligently did not do so. Such speculation would be inappropriate.
In my view, the result reached by the court is unjustified. It is unfair to the defendant and suggests that, in the future, clubs, innkeepers, restaurants, bars, hotels and other purveyors of alcoholic beverages may be held liable for injuries sustained in circumstances not realistically within their control.
The court says, ante at 140 n.10, “The jury could have disbelieved [Moran’s testimony] that he never observed minors drinking what he knew to be sea breezes.” Such disbelief, of course, would not by itself warrant a finding that Moran did observe minors drinking what he knew to be sea breezes.
James Foley testified that he could tell his brothers were “buzzed” that night “[b]y their actions . . . They were laughing about — they were laughing, having a good time, giddy, as it may be. They were . . . just looked like they were having — they were having fun, and they didn’t really pay too much attention to what they were saying or doing in terms of — they just thought everything was funny.” However, my review of the record failed to disclose any testimony that “other teenagers were obviously drunk as the long evening wound down.” Ante at 128-129. In any event, even if there had been such testimony, the jury would not have been warranted in concluding that “[a]t an earlier point in the evening the underage drinking should have been [discovered and] shut down” by Moran.