Ah logic, my frequent companion
Apparently, God probably doesn't exist. Well, it's news to me. Why? Because it's not actually a justified, coherent logical stance. The ASA should in fact hold up this complaint, and you should believe this whether you are religious or not. This is because it is simply not in the power of the British Humanist Association, or any other group or individual for that matter, to assert the probability of God's existence. It's entirely acceptable to say that one does or doesn't believe in God, but to assert as objective fact the probability of the non-existence of something which is substantially outside the human remit of absolute knowledge and understanding is clearly a violation of the code that "marketers must hold documentary evidence to prove all claims". Where is the documentary evidence for the non-existence of God (which is not specified as the Christian God!)? It simply doesn't exist.