I heard about this on Jeremy Vine's BBC Radio 2 chat show a while ago. I think it's disgusting.
They gave many examples of where someone has been the victim of a serious crime but has been denied compensation because they have a conviction for some minor offence many years prior.
The message from the government is that anyone who has made this kind of mistake in their lives is considered less human than others, even if that mistake was a long time ago or if there were mitigating circumstances to the conviction. It is victim-blaming in my mind, saying "you're not really a victim because you did something wrong many years ago".