In Oregon, the driver is cited for an overload violation. I have worked with ODOT, who does the portable weighing. They tell me the amount of overload and I write the cite. The cite goes to the driver and may cost several thousands of dollars, especially on bridges with low weight restrictions. I din't know if your company would volunteer to pay the hefy fine for you.
Where MLK transitions to McLoughlin Blvd headed southbound in Portland is a good example. The weight limit is 10,000 pounds, so no trucks with trailers are permitted. The driver is cited for every pound over 10,000.
If the inability of a driver to stop his truck is related to weight, the driver will be on the hook. But since you are driving for a company, you are covered under their insurance. Any civil penalties will probably be paid for by the company's insurance and you are automatically indemnified (unless they can show you were reckless and purposely disregarded company policy). However, if you are charged criminally, the company cannot do the time for you.
I know it is pretty popular in Oregon for trucks to travel overloaded. I have heard trucking companies say it is more profitable to send trucks through overloaded and pay the fine than to send out another truck.
In time we hate that which we often fear.
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