To add to the above info (which I found useful), I might have understood this wrong but I think breaking the law doesn't necessarily mean it was your fault, either - i.e. the other party may still pay you
The example we are often given is if someone is speeding along a 30mph main road, we are expected to not pull out in front of them; the argument "if they were doing 30mph I'd have had time to pull out" doesn't work and we'd be liable ... i.e. the driver breaking the rules is not deemed at fault
Someone might correct me but that's my interpretation
You are partly right. It gets a bit complicated so I will try and keep it simple.
When it comes to road crashes, there are two aspects of law that come into force. Road traffic law as in criminal law, and civil law which deals with the claim side of the legal process.
If an offence has been committed (as I mentioned in my first post) some elements are called strict liability for example running into the back of another vehicle.(there are exceptions such as being brake tested, but it comes down to proof) but it is deemed as careless driving as the car at the rear is deemed as not having been driven at a distance that the driver was capable of stopping in the distance he/she could see to be clear (tailgating in simple terms) So the driver hitting the rear commits the offence of careless driving and is liable under civil law.
Another example is pulling out of a minor junction controlled by a Stop or Give Way sign/line into a major carriageway and being hit by a vehicle on the major road. The driver has ignored a statutory traffic sign and is guilty of an offence but may still not be fully liable for the cause of the crash.
In this example, the vehicle on the major carriageway may have been travelling well in excess of the speed limit, but under civil law it would have to be established that the excess speed directly contributed to the cause of the crash. If this cannot be established then the driver pulling out would have to accept full liability.
A disqualified driver cannot be on the road legally and cannot be insured, but many do still drive. It has happened many times where the disqualified driver has been involved in a bad crash and been left with life changing injuries due to the negligence and bad driving of a legal driver.
It does not prevent the disqualified driver from making a claim against the legally insured driver as it has been held that whilst the disqualified driver should not have been on the road, had it not been for the negligence of the third party who caused the crash, it is likely that the disqualified driver would have reached his destination in one piece albeit illegally. The disqualified driver would still be prosecuted but the civil claim would still continue with as a claimant.
A motorcyclist who does not wear a crash helmet or more commonly does not have it done u is guilty of an offence.
If a crash occurs caused by someone else, then the court will determine if the fact that the helmet was missing or not done up contributed to the seriousness of the injuries (assuming injuries were sustained) and if so to what degree which is where we then have to look at what is called contributory negligence which means that the driver causing the crash is still held primarily liable, but if it is deemed that the riders lack of helmet increased his risk of injury by (for example) 30%, then the driver of the car will only become liable for 70% of the value of the injuries and the rider will be responsible for the remaining 30% so on a £1000 claim (again as an example) the car driver would only pay out just over £660 of the claim.
There are loads of other examples and I am probably already boring the pants of you, but I hope you get the gist of what I am saying.
Someone who commits an offence and is involved in a crash is not necessarily precluded from making a claim, it all comes down to circumstances, facts, evidence and the nature of the offence committed and even then the actions of other parties also have to be looked at.
The difference between criminal law and civil law is that in criminal law, the burden of proof is beyond all reasonable doubt which is quite a high bar.
In civil law the burden of proof is on the balance of probability of 51% or better so the bar is much lower and and easier to use evidence that cannot be used in criminal law.
Hope that sort of explains things for you?