Vehicle mechanical condition as a cause of accidents

Vehicle mechanical condition sometimes contributes to accidents. Whether or not defective operation of a vehicle will excuse a driver from fault for causing an accident depends on all of the circumstances of the accident and factors such as the following may be relevant:

  • whether the defect was one that ought to have been detected prior to driving the vehicle;
  • whether the “defect” was simply a shortcoming of the vehicle (such as lack of anti-lock brakes) which the driver out to have known about and accounted for;
  • whether, despite the defect, the defendant could have avoided the accident; and
  • whether the accident would have occurred even absent the defect.


Courts have criticized mechanical maintenance being done on an “as needed” basis and have indicated that a more formal scheduled maintenance program is preferable. In Mclaren v. Rice, 2009 BCSC 1457 the plaintiff was seriously injured when the truck he was a passenger in went off the highway. Although there were mechanical problems with the vehicle, the court found that the vehicle went off the road because the defendant momentarily fell asleep. The court rejected the defendant’s explanation that the accident resulted from latent defect in the steering mechanism that could not reasonably have been discovered before the accident, and found that the defendant had not meet the high burden required when the alleged cause of the accident is within the control of the defendant. The court commented on the importance of a proper maintenance program as follows:


Mr. Rice followed no scheduled maintenance of the truck either on a mileage or a temporal basis but rather drove the truck until it did not feel right. I find that such an event driven maintenance program was not taken with a view of preventing the very kind of accident that occurred but was done on an “as needed” basis without any useful or meaningful definition of need.

(Mclaren v. Rice, 2009 BCSC 1457 at para. 27).


The following discussion considers assessment of liability in accidents where particular types of vehicle mechanical defects were involved.


Defective brakes

In Rintoul v. X-Ray and Radium Industries Ltd., [1956] SCR 674 the defendant argued that the accident was inevitable because his brakes unexpectedly failed, but the Supreme Court of Canada rejected that argument, and further held that even after the brakes failed the defendant driver could have avoided the accident by using the hand brake if it had been in proper working order:


In the case at bar the respondents have made no attempt to prove that the sudden failure could not have been prevented by reasonable care on their part and particularly by adequate inspection. They called no witness to explain the extraordinary fact that the service brakes which were working properly immediately before and immediately after the accident and passed satisfactorily the test prescribed in the regulations failed momentarily at the time of the accident. Without going so far as to say that such a story appears to be intrinsically impossible, it is clear that its nature was such as to cast upon the defendants the burden of furnishing a clear and satisfactory explanation of so unusual an occurrence.

(Rintoul v. X-Ray and Radium Industries Ltd., [1956] SCR 674 at 678 -679).


In my opinion, on the evidence the respondents have not only failed to show that the alleged failure of the service brakes was inevitable, they have also failed to show that after such failure occurred Ouellette could not by the exercise of reasonable care have avoided the collision.

(Rintoul v. X-Ray and Radium Industries Ltd., [1956] SCR 674 at 681).


The court also held that failure to prevent accidents caused by reasonably discoverable mechanical defects is negligent:


Driving with defective apparatus if the defect might reasonably have been discovered …are negligent acts which render a defendant liable for injuries of which they are the effective cause.

(Rintoul v. X-Ray and Radium Industries Ltd., [1956] SCR 674 at 678 citing Halsbury, 2nd Edition, Volume 23, page 640, section 901).


Not having antilock brakes is no excuse for having an accident because of failure to stop in time; the driver should be aware of the capabilities of the vehicle and drive accordingly:


[The driver who rear ended the vehicle in front of her in wet weather] suggested that the reason for her inability to avoid impact with the vehicle ahead was due to her vehicle not being equipped with anti-lock brakes.


I find the explanation to be totally unacceptable. Surely, all reasonable and prudent drivers are expected to be familiar with the capabilities and conditions of their vehicles. If they are not, then they should not be driving on public roads.


(Hamhuis v. ICBC, 2005 BCPC 570 at para. 25-26).


Vehicle operators should be familiar with best practices for operation of their vehicle. It has been held that motorcyclists should apply the back brake first, and then the front brake (Dubitski v. Barbieri, 2006 ABCA 304), or to apply both brakes evenly (Cawson v. Quandt, 1999 CanLII 6051 (BCSC)).


Burst tires

In Clements (Litigation Guardian of) v. Clements, 2009 BCSC 112 the plaintiff was severely injured when the motorcycle she was a passenger on crashed after the rear tire burst. The defendant argued that the loss of control was caused by a rapid deflation of the tire resulting from the sudden expulsion of a nail that had punctured the tire and that he was not negligent. Although the defendant was speeding, he argued that the rapid deflation would have resulted in a crash even at a lower speed and that the plaintiff had failed to prove causation. In finding the defendant liable the court held that although the rear tire deflated through no one’s fault, the defendant was driving too fast and with too heavy a load, and that those factors materially contributed to the inability of the defendant to maintain control after the tire deflated.


Wheels detaching

In Lemaire v. Ashabi, 2003 BCCA 527 two plaintiffs were injured when a wheel flew off the defendant’s truck and struck the vehicle in which they were travelling. The defendant had personally installed the wheels on the truck a week before the accident, and had re-checked the nuts a few days after installing the wheels. However, the defendant used a cross-wrench which did not indicate whether the nuts were torqued to manufacturer’s specifications. Hours before the accident the defendant’s girlfriend had heard some rustling in the trees near the driveway where the truck was parked and the defendant argued that thieves trying to steal the wheels had loosened the bolts before being scared off. The Court of Appeal upheld the trial judge’s inference of negligence from the circumstantial evidence presented by the plaintiff and found the defendant liable for causing the accident by not properly maintaining his vehicle. The explanations offered by the defendant regarding thieves loosening the wheel nuts were too speculative to rebut the inference of negligence.


In Gunderson v. Jackson & Leatherwood Log Homes, 2005 BCSC 1204 the plaintiff was injured when his vehicle collided with a wheel that had detached from another vehicle. The court found the defendant liable for not ensuring the wheel nuts were properly tightened and for not stopping after hearing a noise indicating a problem with a vehicle i.e. the wheel rattling off


Cargo not secured

In Michel v. Doe, 2009 BCCA 225 a pedestrian was struck by a baseball sized rock that flew off a logging truck as it travelled down the highway. In dismissing the plaintiff’s appeal the Court of Appeal affirmed the finding of the trial judge that the evidence was equally consistent with the possibility that the rock could have been missed without negligence during the driver’s pre-trip inspection, as with the possibility that it was somewhere it ought to have been discovered during the inspection. In other words, the court found that the plaintiff had not proved that loose rock that flew off the truck and injured the plaintiff was one which a reasonable pre-trip inspection would necessarily have detected, and so the plaintiff failed to prove that the defendant was negligent and the claim was dismissed.




Need help with your claim? Click here for our recommended lawyer.