Why not make him an inside dog so that he isn't alone and bored?Letting him run loose in the neighborhood is never a good idea, not just because YOU may get a fine, but because he could get hit by a car, attacked by another dog or cruel people, picked up by animal control, etc. The neighbors would have every right to make waves, especially if he deficates in their yard or gets too rough or accidentally bites one of their kids. Letting someone else enjoy him isn't what's cruel, making him live outside and then uprooting him from the only family he's known is.

Is there some reason he can't be brought into the house with the rest of the family so that he won't be lonely? Dogs are social pack animals and they are happiest being with their pack--YOU. You may not be unhappy with Chief, but it does sound like, since your son is gone, that you don't want to deal with him anymore. If that's the case then maybe he would be happiest with someone else who would be willing to make him a part of their family. But just remember, there are millions of other unwanted dogs already out there dying in shelters, the lucky ones are living in foster homes that are full to the max with dogs just like Chief waiting for a FOREVER home to come along (which can take a while). And finding a good home for a dog his age is even more difficult.