In Cameron v. State of California (1972) 7 Cal. 3d 318, 326 102 Cal. Rptr. 305, 497 P.2d 777, the plaintiffs were injured when their car went out of control while attempting to negotiate an "S" curve on rural Highway 9 in Santa Cruz. The State submitted proof that design plans had been prepared in the mid-1920's by the county surveyor and that the Santa Cruz County Board of Supervisors had approved the design. However, the plaintiffs submitted evidence that what caused the accident was a "superelevation on the curve that was not consistent across the roadway, but changed abruptly," and that this superelevation was not part of the design plans. ( Cameron v. State of California, supra, 7 Cal. 3d at p. 323.) In denying the State the affirmative defense of design immunity, the California Supreme Court observed that "there is no evidence showing that the uneven superelevation was the result of a design or plan approved by the Santa Cruz County Board of Supervisors. . . . . . . The state merely showed that the Santa Cruz Board of Supervisors approved a design showing the course of the right of way and the elevation above sea level of the white center stripe for the road. The design plan contained no mention of the superelevation intended or recommended. Therefore such superelevation as was constructed did not result from the design or plan introduced into evidence and there was no basis for concluding that any liability for injuries caused by this uneven superelevation was immunized by section 830.6." ( Id. at pp. 325-326.) In other words, in Cameron, what caused the accident--uneven superelevation--was not in the plans. In sum, the driver of a vehicle carrying the plaintiffs lost control of the vehicle after entering a sharp "S" curve on a steep downgrade. (Cameron, supra, 7 Cal.3d at p. 321.) The plaintiffs sued, contending that the curve was improperly graded or banked. (Id. at p. 322.) At the close of evidence at trial, the state moved for a directed verdict due to design immunity. (Ibid.) The trial court granted the motion, and the California Supreme Court reversed. The Cameron court stated: "Plaintiff introduced evidence to show that the design plans contained no specification of superelevation; that the plans merely showed the course of the 60-foot right of way and the elevation of the white center stripe. Therefore, plaintiffs urge that there is no evidence showing that the uneven superelevation was the result of a design or plan approved by the Santa Cruz Board of Supervisors. The rationale behind design immunity 'is to prevent a jury from simply reweighing the same factors considered by the governmental entity which approved the design.' '"To permit reexamination in tort litigation of particular discretionary decisions where reasonable men may differ as to how the discretion should be exercised would create too great a danger of impolitic interference with the freedom of decision-making by those public officials in whom the function of making such decisions has been vested.'" Here the state has presented no evidence that the superelevation which was actually constructed on the curve in question in this matter was the result of or conformed to a design approved by the public entity vested with discretionary authority. Thus, there would be no reexamination of a discretionary decision in contravention of the design immunity policy because there has been no such decision proved. The state merely showed that the Santa Cruz Board of Supervisors approved a design showing the course of the right of way and the elevation above sea level of the white center stripe for the road. The design plan contained no mention of the superelevation intended or recommended. Therefore such superelevation as was constructed did not result from the design or plan introduced into evidence and there was no basis for concluding that any liability for injuries caused by this uneven superelevation was immunized by section 830.6." (Cameron, at pp. 325-326.)