The trial court excluded from the cross-examination of Hodges, the fireman, any testimony as to whether he considered the Thirty-fifth Avenue Crossing a particularly bad crossing. The exclusion of the fireman's testimony requires us to examine our recent holding in Wolfswinkel v. Southern Pacific Company, 81 Ariz. 302, 305 P.2d 447, for it is the authority on which defendants rely to support the ruling of the court. The question of the admissibility of Hodges' testimony in this aspect was raised at a pre-trial conference at which seemingly the trial judge specifically prohibited any examination at the trial which would elicit testimony that this was a "particular bad crossing."

Two distinct but interrelated questions must be considered with reference to contributory negligence instructions: first, instructions which purport to define contributory negligence in terms of specific conduct, and second, instructions which deal with the jury's duty subsequent to its determination that the facts in issue do in fact constitute contributory negligence. The leading case representing the former proposition is Wolfswinkel v. Southern Pacific Company, 81 Ariz. 302, 305 P.2d 447 (1956), amplified, 82 Ariz. 33, 307 P.2d 1040 (1957); for the latter, Layton v. Rocha, 90 Ariz. 369, 368 P.2d 444 (1962). DEFINITION OF CONTRIBUTORY NEGLIGENCE

The first time the plaintiff objected to this instruction was when she filed her motion for a new trial. The plaintiff contends that the giving of this instruction violated Article 18, Section 5, of the Arizona Constitution, A.R.S., citing Wolfswinkel v. Southern Pacific Company, 81 Ariz. 302, 305 P.2d 447 (1956), on rehearing 82 Ariz. 33, 307 P.2d 1040 (1957), and that the giving thereof was such "fundamental error" that it can be raised without having objected to same at the time of settling instructions, citing Trojanovich v. Marshall, 95 Ariz. 145, 388 P.2d 149 (1963). "The defense of contributory negligence or of assumption of risk shall, in all cases whatsoever, be a question of fact and shall, at all times, be left to the jury."

¶ 22 Jury instructions in violation of Article XVIII, Section have uniformly been held to warrant reversal. See Trojanovich v. Marshall, 95 Ariz. 145, 146, 388 P.2d 149, 150 (1964); Michie v. Calhoun, 85 Ariz. 270, 274, 336 P.2d 370, 374 (1959); Wolfswinkel v. Southern Pacific Co., 81 Ariz. 302, 307, 305 P.2d 447, 450 (1956); Salt River Project Agric. Improv. and Power Dist. v. Westinghouse Elec. Corp., 176 Ariz. 383, 389, 861 P.2d 668, 674 (Ariz.Ct.App. 1993). These decisions, it is true, were rendered prior to the adoption of comparative fault in Arizona.

Plaintiffs contest the correctness of the various instructions given by the trial court on contributory negligence, and also argue that the issue of contributory negligence was overemphasized to the prejudice of plaintiffs. First, plaintiffs contend that it was error to give an instruction on contributory negligence which contained the words "then I instruct you that he was negligent." They argue that these words have been held improper in Trojanovich v. Marshall, 95 Ariz. 145, 388 P.2d 149; Layton v. Rocha, 90 Ariz. 369, 368 P.2d 444; Wolfswinkel v. Southern Pacific Company, 81 Ariz. 302, 305 P.2d 447, etc. These cases do not support their contention.

[12] The care [12] "From the lack of regulations the jury might infer that the corporation commissioners were of the opinion that a flagman, gates, automatic signals or warning or protective devices or a lower rate of speed than 79 miles per hour were unnecessary to reasonably protect the traveling public at the Thirty-fifth Avenue Crossing. The opinion of the commissioners if offered in person is expressly prohibited by Wolfswinkel v. Southern Pacific Company, supra. [ 81 Ariz. 302, 305 P.2d 447] An inference as to their opinion, which inference may be contrary to the facts and cannot be rebutted, is to be doubly condemned." (Footnote in original).

Michie v. Calhoun, 85 Ariz. 270, 336 P.2d 370 (1959). In Wolfswinkel v. Southern Pacific Co., 81 Ariz. 302, 305 P.2d 447 (1956), affirmed on rehearing 82 Ariz. 33, 307 P.2d 1040 (1957), we held that the court may not instruct the jury that if it finds certain facts in issue to be true, it must find the plaintiff guilty of contributory negligence. The instruction given in that case was the following:

However, under Arizona's constitution the legal and factual issues of contributory negligence by the plaintiff are questions for the jury. Wolfswinkel v. Southern Pacific Co., 81 Ariz. 302, 305 P.2d 447 (1956) affirmed on rehearing 82 Ariz. 33, 307 P.2d 1040 (1957); Michie v. Calhoun, 85 Ariz. 270, 336 P.2d 370 (1959); Layton v. Rocha, 90 Ariz. 369, 368 P.2d 444 (1962). At the trial of this case the court gave an instruction on the principles of last clear chance.

Ariz. Const. Art. 18, § 5, A.R.S. We have also held that the court may not instruct the jury that if it finds certain facts in issue to be true, it must find the plaintiff guilty of contributory negligence, Wolfswinkel v. Southern Pacific Co., 81 Ariz. 302, 305 P.2d 447 (1956), affirmed on rehearing 82 Ariz. 33, 307 P.2d 1040 (1957). In the present case the following instructions were given over the objection of the plaintiff:

It thus becomes quite evident that thereafter in the light of the speed of each plane, the defendant could not have had a last clear chance of avoiding a collision with the plaintiff by the exercise of reasonable care. Plaintiffs next contended that defendant Marsh's instructions Nos. 4, 5, 10, 25, and one of the court's instructions are in conflict with the case of Wolfswinkel v. Southern Pacific Co., 81 Ariz. 302, 305 P.2d 477; Opinion on Rehearing, 82 Ariz. 33, 307 P.2d 1040, regarding the constitutional prohibition on contributory negligence as that prohibition bears on jury instruction. This Court is not required to review the propriety of the foregoing instructions as the plaintiff did not direct the trial court's attention to the errors specified by stating distinctly the matter to which he objected and the grounds for his objection as required by Rule 51(a), Rules of Civil Procedure, 16 A.R.S., which provides as follows: