<p>The plaintiffs jointly managed a hog raising business. The defendant was a corporation managing national motorways on behalf of the Minister of Construction and Transportation. It expanded a section of a national highway that passed next to the said hog farm, thereby reducing the distance between the hog farm and the national highway to about 25m. As a result of the increase in noise and vibration from the expansion of the highway, the hog farmer had to shutdown his hog raising business. The Supreme Court had to analyze the standards for the determination of illegality. It held that illegality, which was a requisite for torts, should not be determined based on all of the relevant acts as a whole, but determined based on the acts in question on an individual and relative basis. Therefore, even though a facility was lawfully operated or offered to the public, the illegality of inflicting damage to a third party as a result of hazardous exhaust material should be determined separately and the standard for determination in such case should be whether the hazardous level exceeded that which was ordinarily experienced in social life. It was of the view that the degree of infringement upon the plaintiffs’ hog raising business exceeded that which was, in light of social norms, ordinarily tolerated. Therefore, although the nature of the use of the highway and the traffic on it was for the public interest and the noise and vibration from the traffic was inevitable, the defendant could not escape from the responsibility for the damage to the plaintiffs as a result thereof. In the case of damage resulting from environmental pollution caused by a place of business or such, since the concerned business person was required to compensate for damage even if there was no cause attributable to such person and the said environmental pollution included the harm inflicted upon a person’s health or the environment by noise and vibration, the business person was required to compensate for damages incurred by the injured party even though there existed no cause attributable to such business person. The judgment of the court below was reversed.</p>