“2 Vehicles Turning Left Into Private Drive”

4 lane road with a left turn lane. traffic lights approx. 150m or more further up road. left turn lane packed, no one moving. No oncoming traffic, driver a pulls left but has to travel several meters up along vehicle b, as vehicle a starts turning into private driveway, vehicle b starts turning and hits vehicle a on side. Vehicle a was on oncoming traffic side but mid turn. Who is at fault. Vehicle a is a newer vehicle, approx. $1000 damage, vehicle b not worth $1000 but insists damages are closer to $1500

I believe it to be 50/50, one officer stated 75% wrong for vehicle b

What is the consensus here.

Fault determination for insurance purposes is determined through the Ontario Fault Determination Rules