I am being sued due to a car accident, it was my fault, but I want tocounterclaim because the other driver was onher phone?

Every personal injury case requires both negligence (including comparative negligence) and injuries. Regardless of the fault issue, you must have a significant enough injury to warrant making a claim for damages (I assume you are not talking about just a property damage claim?).  You also mentioned you were at fault. If there other driver was on the phone but that was not a contributing cause of the accident, it does not matter. If you did suffer injuries and you believe the other driver was partially at fault, you should contact an experienced personal injury lawyer in your area.  good luck