Older housebroken dog urinating inside

Question
I recently moved in with my girlfriend who has a 12 year old Pekingese. The dog was house broken for years and before I moved in started urinating in one place when no one is around. The dog has been checked and in perfect health. My girlfriend will not scold the dog because she never catches him in the act, so ends up doing nothing about the problem. She will let him out at night and he will pee just a couple hours later, so it is not an issue of him not being let out enough. Again, it was before I lived there and he has been checked thoroughly for health issues. When I come in, and he has peed, he cowers and looks ashamed. The dog is very willful, will not come usually when called, and is very somber. He has been on a multitude of psychiatric pills and none of these have worked either. I encouraged her to take to the place he peed and scold him, and then let him out. She disagrees, and says if it is after the fact, then he won't know what he is being scolded for. What do you think is the problem, and what should be the correct course of action?

Answer
This is a difficult problem, and may not have a good solution.  12 years olds are very set in their ways.  I notice the older dogs get, the more interested in sniffing an marking they become.  For a younger dog, I would suggest better leadership and obedience training.  The key to most behavior problems is approaching things using the dog's natural instincts.  Dogs see all the people and dogs in the household as a pack with each having their own rank in the pack and a top dog.  Life is much easier if the 2 legged pack members outrank the 4 legged ones.  You can learn to play the role of top dog by reading some books or going to a good obedience class. A good obedience class or book is about you being top dog, not about rewarding standard commands with a treat. Start at http://www.dogsbestfriend.com/  For more on being top dog, see http://www.dogbreedinfo.com./topdogrules.htm

One thing that could make a dramatic difference would be to neuter him if not.  It is no cure all, but combined with a good pack structure, it could fix it.  

I think you need to crate him whenever nobody can watch him.  The dog may be
happier in its den than loose in the house.  It relaxes, it feels safe in its
den.  It rests, the body slows down reducing the need for water and relieving
its self.  Dogs that have been crated all along do very well.  Many of them
will rest in their crates even when the door is open.  I think the plastic
ones give the dog more of a safe, enclosed den feeling.  They are harder for
dogs to open too.    Metal ones can be put in a corner or covered with
something the dog can't pull in and chew.  Select a crate just big enough for the full grown dog to stretch out in.

Leave it some toys.  Perhaps a Kong filled with peanut butter.  Don't leave
anything in the crate the dog might chew up.  It will do fine without even any
bedding.  You will come home to a safe dog and a house you can enjoy.

A dog that has not been crated since it was little, make take some work.
Start out just putting its toys and treats in the crate.  Praise it for going
in.  If you have been able to trust it with any bedding, put that in the crate.
Feed it in the crate.  This is also an easy way to maintain order at feeding
time for more than one dog.

If he urinates in the crate, put a grid in it. They are available with the crates, but expensive and hard to find. A piece of closely spaced wire closet shelving from a home supply place is cheaper. I am now using a plastic vegetable bin with plenty of holes drilled in the bottom.  

When you are there, keep an eye on him.  Close doors, put up gates, whatever to keep him where you can see him.  If you catch him in the act, give him a sharp ''Ut, ut, ut!'' and run him outside.  In most cases, it is a waste of time and abusive to punish a dog unless you catch it in the act.