NSW Car Accident on Motorway - Who is at Fault and Liable?

[Fourcarpileup]

My partner was in a four car pile up, on a motorway car accident. It was a 100km/h zone. Apparently there was a 5th car that was pulled up for no apparent reason who had no damage but was the reason the pile-up happened. However, my partner did not see another car as he had driven off before anyone got or gave details. My partner was in the 3rd car and apparently pushed the 2nd car into the 1st car. However, another car also ran up behind him.

Our car is insured, the 2nd car is not. Can anyone help me with who is at fault under Traffic Law? Who is liable for damage costs of which vehicles? We have a claim that is currently in progress, but both the 1st and 2nd cars are now trying to claim off it.

I'm not sure if it makes any sense, but all information is welcomed. Thanks

 

[JS79]

If another car ran up behind him that car would seem to be likely liable for your partner's damage as they did not give enough space to break - hence your partner would more than likely be liable for car 2 and car 2 liable for car 1 all for not giving enough space to break.

 

[Fourcarpileup]

That was our understanding also. But car a and b are both claiming on our insurance as car b doesn't have insurance.