This was discussed on Jeremy Vine's Radio 2 show yesterday and he actually spoke to Mr Houston about the day his daughter died and his campaign to have the man deported. My respect for Mr Houston has more than doubled after listening to him because of his composure, he seemed very level headed about what he knew of the law, he wasn't demanding execution or ranting and raving; he simply wanted to know why this man was behind the wheel when he shouldn't have been, and how he has been able to walk away from so many crimes and still live a free man. He is a very strong man to not want to rip the guys head off.
I find it so sad too that man has had two children (most likely not out of love) to stay in this country, while Mr Houston no longer has a family and cannot do so, where is the justice in that? Cameron has once again let people down again after writing to this man during the election campaign saying he would help. None of that from him as of yet but I wouldn't have expected better.
If you are going to live in this country then it is only fair that you abide by our laws, try to make a living for yourself and generally live as a respecting citizem of the UK - otherwise the door should be shut.