For example- where on your car did the other driver impact? Where in the intersection did the impact occur? Were there any skid marks? Was there a green arrow on the light? Or was it just three balls?
I'm not a Utah attorney, but I understand that Utah uses a "comparative" negligence standard, where if your wife was less than 50% at fault, she can still recover for her injuries. If she was 50% or greater at fault, she will not recover anything for her injuries.
Also, Utah has PIP auto insurance coverage. You should talk to a good Utah attorney to fully understand how this affects your wife- but there will be insurance coverage for the first $3,000 in medical bills at least- no matter who is at fault.