2) Two Moslems get married and agree in their pre-nup contract that legal issues involving their marriage will be governed by Sharia. Some time later, one of the parties gets tired of being wife No. 4 and goes to a government court to argue that her pre-nup contract was unreasonable to the point of being invalid ab initio. How should the government court rule?
In this case the government court would have nothing to say since both parties agreed & _contracted_ that Sharia would be the basis for rulings in this marriage. So long as the female in question was above the age of consent per the laws of the state & was not influenced in any way to sign her consent to the governance by Sharia then she's screwed.