When is contributory negligence not a factor in determining liability?

When a case of absolute nuisance shall be here, there will be need to determine whether contributory negligence in any sense is a factor to be weighed in determining liability. The factor is not eliminated by saying that to make out contributory negligence in situations of that order the conduct, if attributed to a man of normal understanding, must betoken indifference to consequences, known or unknown. This may be merely to say in other words that there is a duty of reasonable vigilance in proportion to the risk. Very often, something close to indifference must appear though the basis of liability is nuisance growing out of negligence. McGuire v. Spence, supra. There are times even then, a we have already pointed out, when fault must approach a complete abandonment of caution to make out the absence of ordinary care. We leave the question open whether, in cases of absolute nuisance affecting travel on a highway, the test is greatly different.