Auto Insurance Claims: rear end collision extenuating circumstances, lane traffic, extenuating circumstances

Question
I rear ended a car that had panic stopped in the left lane of a three lane traffic light controlled intersection due to cables in the road. The light was green and no other traffic had stopped, so I had no warning or reasonable expectation this would occur and was traveling 2-3 seconds behind the car. I noted the green light, began to proceed into the intersection and then saw the vehicle suddenly hard stop in front of me. I was unable to fully stop and struck the rear of the car going approximately 5-10 mph.  I didn't see the cables in the road until I hit my brakes and no other vehicles stopped or slowed in front of the lead vehicle. No airbags deployed. Insurance company is attributing all fault to me. Do you think this a reasonable determination given that the lead driver didn't obey the green light and stopped abruptly for no apparent reason?

Answer
Unfortunately, you are responsible for the control of your vehicle at all times. However, the cables in the road may have contributed to your inability to stop your car in time. Find out who was responsible for leaving them and ask them about paying for the damage they caused.