Hi There Cliff,
I was involved in a similar situation which resulted in an accident about 20 yrs ago. Long story short; It all came down to convincing/demanding that the OPP officer inspect the truck drivers signal/brake lights. They were not working and the truck driver was charged. My Integra was pinned underneath the trailer with me in it and I was able to get out of the car without a scratch. It all came down to the officers discretion (on checking the brake lights) as it seemed that he was very sympathetic to the truck driver and was reluctant to ticket him.
On the insurance side, Mrs. Slayer, all knowing insurance babe/love of my life says;
Without an officer issuing a charge/ticket against the offending driver, you would be considered at fault and both claims for damages would go against your insurance.
I'm seriously thinking of installing a camera in my car. Too many shenanigans going on on GTA roads that make the good drivers vulnerable for liability.
Regards,
Simon
p.s. a big hello to Sue too.