Because he is, or at least was, part of the insider clique.
Even as late as 2014 he was still allegedly close enough to the Clintons that he and Bill could have a personal phone call hours long.
Seriously though, it is self preservation for the judge. If Trump loses, no harm in sentencing him punitively. If he wins, might as well sweep it under the rug to try and save a few lives of you and your staff.