dissenting.
Ordinarily I would be reluctant to dissent in a diversity case, but here my reading of the record is so contrary to that of the majority that a dissent is required. It seems clear to me that Raymond Campbell fell when a lacing broke, causing him to fall to the ground, rather than simply slipping and falling off the boom while threading the crane.
The plaintiffs tried this case on a failure-to-warn theory, and American defended on the same theory. The district court instructed the jury on that theory, and neither party objected to the wording of the instruction. There were two aspects of plaintiffs’ failure-to-warn theory: (1) that American failed to adequately warn Campbell of the danger of threading the crane by walking on the boom while carrying a cable, and (2) that American failed to warn Campbell that a strut could break under Campbell’s weight.
Campbell presented both theories in Count III of his Second Amended Complaint and throughout the trial. The complaint reads, in relevant part:
That while walking across the braces/ struts of the boom of the aforementioned crane and while in the process of threading same, one of the braces/struts upon which Plaintiff was walking broke.
*1334a. The brace/strut upon which Plaintiff was standing at the time that he fell was not properly welded;
b. The weld of the brace/strut that Plaintiff was walking on at the time said brace/strut was welded was not properly inspected;
c. Plaintiff was not given adequate warning of the possibility that the braces/ struts of the crane could break under Plaintiffs weight;
f. Failed to require that the welds of the boom be periodically inspected by means of magnetic particle inspection or other non-intrusive inspection methods other than mere visual inspection.
Second Amended Complaint, at 1-2, 5.
In his opening statement, Campbell’s counsel stated:
On the day that Ray got hurt, what happened was one of these lacings broke. It broke, there is no dispute that it broke. Ray will testify that it broke. He was on it, and even though the person that reweld-ed it is deceased — -he died, he just died— you can see that there is a new weld there where it had been refastened.
Tr. 89-90.
Counsel for American responded:
As you can see, the location of the broken lacings was some ten feet from the place where that timber was located. The place where the lacing was broken that he apparently stepped on that simply gave was located 14 inches from where a timber should have been which shows that when that cable came down and snapped that lacing and damaged it, much of the same manner that you can see in these photographs, apparently the repeated slapping and damage of the lacing caused the lacing to break. When he stepped on it, obviously the lacing was broken. The weld may not have been broken because it’s much stronger than the lacing, but the tubular steel simply gave as a result of the repeated damage to the boom’s lacings.
Number four, that as a result of that and the damage which we will show you occurred, those lacings were weakened, and the one lacing was obviously cracked because when he stepped on it and it broke, down he went. So we think at the conclusion of the case you will agree that this man was injured not because somebody failed to warn about walking on the boom or failed to warn or failed to tell them how to carry the cable from one point to another, but because of the misuse and abnormal use by using the crane without the timbers resulting in damage to the crane which was never repaired. Mr. Campbell will tell you know [sic] one routinely inspected the crane. The crane was just used and it was used in that damaged condition. We think that will be your conclusion at the end of the case, and if it is, we will ask you to return a verdict for the defendant.
Tr. 108, 113.
During the trial a conflict developed as to the plaintiffs’ theory of the ease. The following colloquy occurred during plaintiffs’ examination of Donald E. Alberts, American’s chief design engineer:
[Mr. Leeds]: So before this crane was manufactured you had knowledge about the method in which people were threading the crane by walking across the boom?
A. That’s correct.
Q. And you will agree with me, won’t you, sir, that it is foreseeable that an individual walking across this boom pulling a heavy rope that it is foreseeable that there is a potential they could fall?
MR. MENGHINI [counsel for American Crane]: Your Honor, I will object that it’s irrelevant to the issues in this case. We are talking about falling off the crane.
MR. LEEDS: It’s absolutely not irrelevant. Can we have a side bar on this?
[BENCH CONFERENCE.]
MR. MENGHINI: The plaintiff didn’t fall. A lacing gave and he fell through. That’s the case that we are trying. This is not a situation where he slipped and fell off the crane. So what difference does it make? Not only that, he is asking him for an opinion which the jury can form without *1335him opining on it and he has not been designated as an expert witness to do.
MR. LEEDS: My case, judge, is that this guy should never be out there regardless of what caused him to fall, whether he slipped and fell or whether a lacing broke. That’s my case.
THE COURT: No. Your case is the specific facts, which in this situation is that this weld gave loose on the boom. The real problem that I see, however, is that you are asking him for expert opinion. He has not been designated as an expert and Ray Charles could see that you have a potential for falling off of anything that you are walking on, so we don’t need an expert for that.
MR. MENGHINI: Can I speak to that, Your Honor, just momentarily? I have prepared a brief for the Court in support of a motion for directed verdict which addresses this very point. If that’s his ease, Missouri law is crystal clear that you don’t have to warn of the obvious, and you just made the point that anybody can be asked can you slip and fall off the crane, so we are going to address that issue sooner or later.
THE COURT: Yes, but it’s obvious that you can fall off anything. I don’t know that that requires a directed verdict, because you have the situation with the cable. So that’s an additional factor there, and as to whether or not that’s a safe procedure and whether or not the company should have been advising people how they should do it, but I think it’s obvious that anybody can fall off anything.
Tr. 190-93.
Mr. Alberts then continued his testimony:
[Mr. Leeds:] Sir, when you went out there you knew that this case was about a man falling due to an alleged lacing breaking, correct?
A. Yes.
[MR. MENGHINI:] Mr. Alberts, counsel on direct examination asked you if it was possible for a weld to have a crack in it which would go undetected and I think you said yes, it’s possible.
A. Yes.
Q. In this case do you understand that Mr. Campbell’s testimony has been that he was walking along the boom when he put a foot on the lacing in question and the lacing collapsed; is that your understanding?
A. That’s correct.
A. I was looking at the lacing that I was told had failed and I was looking at the welds trying to identify whether the welds looked like they were solid or defective and structural integrity of the boom and the rest of the welds on the boom to see if they were solid welds or defective.
[MR. MENGHINI:] The complaint that was filed in this case that we had available to us before we went out there, did that contain a complaint at that time that the welds were bad?
A. That’s correct.
Q. And that somehow the welds had something to do with this lacing failing?
A. Yes.
Q. Now, when you examined the particular lacing that faded here, could you tell — well, first of all, the lacing was repaired. I think you testified it was reweld-ed?
A. Yes.
Q. Could you tell from your examination whether it was the weld that failed or the lacing that failed?
A. It was impossible to tell because the repair that they had made covered up exactly what had happened. It destroyed the evidence.
Q. So you have no idea in this particular case whether it was a damaged lacing or a weld that was damaged that failed to cause the failure?
A. I couldn’t tell from looking at it.
Tr. 199, 203, 208-09, 232 (emphasis added).
Shortly thereafter, during a bench conference, counsel for American repeated:
*1336There is no duty on the manufacturer to warn somebody that they might fall off the crane. The problem with that is that he didn’t fall off the crane. We are trying something here that is a lacing that gave way.
Tr. 249.
American argued that the strut broke because Campbell’s employer failed to properly use and maintain the crane, and thus American, the manufacturer, bore no liability. American’s counsel asked the following of engineer Ronald M. Kohner:
Q. Do you have an opinion, sir, as to whether the absence of the timber at or near the place where the lacing failed had anything to do with the failure of this lacing that caused Mr. Campbell’s injury?
A. My opinion is that if the timbers had been in place, this damage that we see on much of the boom could not have taken place, and in my opinion that’s the damage that caused the lacing to fail when he stood on it at a subsequent time.
Tr. 303.
The record in this case makes it abundantly clear that the plaintiffs’ claim was not simply “that Campbell should never have been on top of the boom because of the danger that he might fall off’ as the majority characterizes it. Rather, it was a two-fold claim that American failed to warn as to two dangers, neither of which was obvious. American defended each of these claims. First, it argued that threading the crane by walking on the boom while carrying a cable was an obvious danger. Equally important to American’s defense, however, was the additional argument that the crane itself was safe as manufactured, that it was damaged by misuse, and that but for the misuse, the lacing would not have broken under Campbell’s weight and Campbell would not have been injured.
The jury heard all the evidence and rejected American’s defense. We should not upset the factual findings made by the jury after it received a failure-to-warn instruction that neither side objected to; above all, we should not do so on a theory that American did not advance at trial. For American to argue on appeal that there is no evidence in this record that Campbell fell because a lacing broke is disingenuous and must be rejected.
The jury may have rejected the plaintiffs’ failure-to-warn theory regarding walking across the boom — concluding that the danger was so obvious that they should not be permitted to recover on that theory — but accepted plaintiffs’ theory that American’s failure to warn of the danger of a strut breaking was not obvious, thus deciding that the plaintiffs were entitled to recover on that theory. This possibility is not a basis for reversal in this case. American made no effort at trial to have the court give the jury separate instructions on the two failure-to-warn theories. Rather, American argued, on the one hand, that the danger of slipping and falling while carrying the cable across the boom was so obvious that recovery must be denied on that theory; and, on the other hand, that American could not be liable under the theory of failure to warn of the likelihood of a strut breaking because the damage to the strut was caused by Campbell’s employer rather than any manufacturing defect or any failure to warn of a defect in the strut. In my view, we should affirm the district court in all respects. Accordingly, I dissent.