Are you saying that one is free to commit any crime as long as one day they stop and no longer commit crimes?
And no punishment or retribution is required?
However, because we want people to come clean of their own agency (both to make crime-solving take up less public resources, and to make it such that criminals don't have to wait to get caught before becoming productive and non-harmful members of society), we should adjust incentives such that the punishment for coming clean of one's own accord is a little less, and the punishment for getting caught for the same crime is a little more.
Maybe it could be implemented as adding an extra punishment for concealing a crime?
For all we know he could have been operating a human-smuggling operation from his current local.
Either way he knowingly and purposefully avoided prosecution.