Thanks Canuck. This is a dog that was well trained and rarely if ever had a problem with going outside to do it's thing. He seems to have chosen to disobey, it's not like he suddenly forgot. The new dog is trained to pee on command and does fine. I think it's more complicated than just training, but I'm no expert.
I am no canine behavioural expert either but the idea here is to replace/modify a negative behaviour with positive re-enforcement which re-asserts your's and your family's alpha position. It appears your dog's current behaviour is a form of acting out against the pack for bringing a new dog into the pack.