What is the test for the defence in a motor vehicle accident case?

15 As in National Trust v. Wong, the trial judge here held that there were explanations as consistent with no negligence as with negligence: . . . the defence has succeeded in producing several different explanations of the accident which are equally consistent with no negligence on the defendant's part. It may be that the vehicle swerved to avoid an animal or debris, hit the pool of water and hydroplaned. It may be that the vehicle swerved on the highway in a last instant effort to avoid the pool of water itself and hydroplaned and lost control. It may be that in a sudden gust of wind, the vehicle was jerked and lost control. The vehicle tire may have hit a rock or other object, blown out and the vehicle lost control.