i think by the definition of accident containing the word unintentional there could be 100% of these

yes' there is'

It sounds ridiculous, doesn't it! I guess the only kind I can think of is one that was caused by a natural disaster (e.g. tornado, earthquake), thus clearly out of any person's control, even if a bunch of cars did collide with one another.

Yes ... but not usually ... but here in Quebec, we have automobile insurance that is strictly "no fault" ... despite the fact that the vast majority of vehicle accidents are caused by human error.

I believe that a "no fault" accident is one in which fault cannot be determined based on the information gathered at the scene of the accident.

No. If two or more vehicles are involved in a crash....... SOMEONE caused the crash. It can be from a mechanical problem to a human problem.

cyndi thanks for stepping into the Kedar question and calming things down. There are very few things in life that make me lose my temper and I apologize for doing so:(...this was just a little over the top for me.

If two cars are parked on directly opposite sides of a parking lot lane, proceed to back out at the same time at the same rate of speed, and bump rear ends then each would be responsible for their own damages. This would also apply to vehicles that simultaneously change to an unoccupied part of a lane between them and collide. In the above examples, I would say that both drivers are equally at fault but by virtue of that, neither driver is considered to be exclusively or more at fault. I'd say that if a natural disaster causes an accident, then that would be a no-fault accident. E.g., if Mt. Rainier erupts, launches a boulder directly into the path of a moving vehicle on Interstate 5, and the vehicle collides with the boulder, then no living being is at fault. According to http://www.scherandbassett.com/CM/FSDP/PracticeCenter/Personal-Injury/Motor-Vehicle-Accidents.asp?focus=topic&id=4 : "When a driver has been in an accident, no-fault auto insurance allows the driver to collect from his or her insurance company no matter who was at fault. Not every state has a no-fault insurance structure, but those that do have very specific laws governing when, how much and for how long the injured party may collect. Consult with an attorney to discuss how your state views fault and to determine how the laws may affect your right to recover damages for injuries. How No-Fault Insurance Works No-fault insurance is a system in which auto insurance pays benefits the insured driver in case of an accident. The insurance compensates the insured driver for monetary losses, no matter who was at fault. This is contrary to systems in which the at-fault driver’s insurance company must pay the bulk of the compensation after an investigation and determination of fault by the insurance companies or the courts. The system is designed to streamline the process of payments to injured people and to lower the burden on the courts. Under the no-fault insurance system, it can be more difficult to sue an at-fault driver for damages; the insured typically must have been quite seriously injured in order to take such legal action. On the other hand, monetary recovery for the insured is more certain under no-fault insurance because the compensation is immediately available through the insurance policy of the injured party. No-fault insurance policies often have a cap on the compensation they will pay. The no-fault insurance system prevents injured parties from receiving a windfall due to the accident, but it also ensures compensation no matter who caused the accident. In a no-fault state, the other driver will also receive compensation from his or her insurance company if that driver sustained certain economic losses. The specifics of no-fault insurance laws vary widely by state." Re: "Under the no-fault insurance system, it can be more difficult to sue an at-fault driver for damages; the insured typically must have been quite seriously injured in order to take such legal action." I've had 2 accidents that weren't my fault, where I was able to recover payment for my damages that weren't covered by my insurance, through small-claims litigation.

Sure, there are. However, accidents which are truly 'no fault' are probably a fairly small fraction of the total. 'No fault' means just that: the accident occurred through no fault of any party involved because they were taking all reasonable precautions under the existing conditions at the time of the accident. Here are some examples: 1) Driving along at the posted speed limit on a well maintained road in clear, dry weather conditions. A manhole cover plate flips up as you drive over it, causing a wheel to be damaged and throwing you across lanes into oncoming traffic, causing a multiple car accident. No reasonable action taken by any person in this example could have avoided the accident. 2) Driving along the same road at the same posted speed limit, but now the road is wet due to rain. You skid, end up in the opposing lane causing an accident. This is NOT no fault. This is driving too fast for conditions, which lead to the accident. 3) Driving along the same road at the posted speed limit and a front tire blows out, causing you to end up in the oncoming lane causing an accident. This might or might not be no fault. If the blowout was due to non-visible debris, like glass or nails, then it's no fault. If the blow out is because you were not properly maintaining your tires, it's your fault. Determining fault may not be as simple as it sounds. In fact, some determinations may be based upon subjective or incorrect evidence. But the reality is that very few accidents can really be called 'no fault' when all things are taken into consideration. But yes, there are 'no fault' accidents.

Comprehensive claims - vandalism, acts of God, weather, and animals are automatically 0% at fault for the driver.

If a driver that was having a heartattack caused a collision, they would be deemed not to be 'at fault' because they could not make rational decisions, however it does not take away their insurers liability. The insurance company would have to pay, but the driver probably would not be cited

There's no accident that could not be avoided unless nature cause a bolder to drop in front of you, however if that happened, there is no reason any other car would be involved, another car should be able to avoid the accident.

Brian's and the Chief's answers are the best and most thorough answers to your question. I cannot improve on those. All that I can offer is really another shade of the same subject. Contributory negligence is a label that is placed on some accidents that are not the primary fault of one of the parties, but evidence behaviors that have factored into the accident. Contributory negligence determinations reduce the amount of money paid out. Beyond that. when I was teaching traffic safety to county employees in the SF Bay Area, it was noted that the county's criteria for evaluating responsibility in accidents involving county owned vehicles was the question, "Was this accident preventable?" An employee may not have caused the accident, but could have prevented it. That is noted. It is a rather useful doctrine because it p[romotes defensive driving and the development of hightened awareness and safety consicousness. If I am bleeding and in pain, I am not comforted by thge fact that it was the other guy's fault :)

Sure there are. Chief and Brian have pointed out a couple, as have others. However, lawyers will ALWAYS try find a way to blame someone. For example: The manhole cover example: They would try to blame the workers who last put the manhole cover back on, and the city/county for not foreseeing the damn thing would "flip" like that an cause the damage. The "invisible debris" example: They would try to blame the street/highway department for not keeping the road clear of debris. (They'd most-likely try to blame them for deer and other animals running onto the road, causing an accident, too. Couldn't they have foreseen this and put up high-enough fences?)

No. Someone is always at-fault for causing a motor vehicle crash.

who is at fault here? a motorist driving along motorway hits debris in the road causing a tire blowout, motorist loses control for brief while swerving across lanes and finally coming to a stand still without hitting anything onto the hard shoulder. Along comes a truck that has swerved due to the traffic ahead swerving to miss the car involved and it rear trailer clips the car on the hardshoulder and writes the car off completely. Who is at fault here?

2nd Answer: I have read all the anwers posted here and some are pretty convincing. Two things to remember: an auto accident has to involve at least two or more vehicles. one crashing with the other(s), a single vehicle accident or property damage. If an item falls off a moving vehicle and strikes another moving or stationery vehicle, this is not an accident this is property damage. a good example is a deer hit on the interstate or a rock hits your windshield from the dump truck ahead. auto accident? no. property damage. There is always a reason why two or more vehicles crash into each other. Someone, whether its you or the other driver or the government is always at-fault.