I was asked to pay a sub contractor $3161.96 because my General Contractor did not pay his sub contractor. I paid my GC the entire contract value

You are not required to pay the sub because you already paid the general, ASSUMING (1) you properly withheld 10% of the payments to the general (this is called retainage) and (2) you have not recived a letter from the sub demanding that you withhold all future payments to the general (this is called a funds trapping letter). The most that you should be liable for (in most situations) is 10% of the amounts you paid to the general. This is a fairly complicated area of law and this general advice may not fit your fact pattern. That could chanbe my answers.   Mark P. Brewster Brewster Law Firm mark@markbrewsterlaw.net (210) 437-1232