@Ben Nelson
This is always a touchy subject. I have more than a couple of investor friends who actively seek people with criminal and S.O. backgrounds as a part of their ministry. They believe in giving second chances to men who have messed up bad but are sincere in making a better life with better choices. They lay on time, work hard and take care of the properties they live in. S. O.'s face a harder stigma, most want to move on with life from something that may have happened 20+ years ago, but can't because of the public stigma.
Personally, I've met a good number of these men, as I volunteer at a local prison ministry, and see how they change their lives when they get out. But, having this kind of involvement isn't for everyone. All I can say is, let your heart and common sense guide you. If this guy has turned his life around and just needs a place to live without persecution, what's the harm. Be the clear headed one.