User blog comment:FairyRaven/Fairy Tail Chapter 353: Exorcism, Review and Commentary/@comment-4489126-20130927121241/@comment-7418318-20130927121844

Being a member of a Dark Guild isn't necessarily making him a complete bad guy.

More likely he doesn't really care for good and evil, as long as it get's him closer to the next demon to kill, just like Jellal is ignoring the law so he can fight the Dark Guilds. If you ask the Mage Coucil I'm sure they'd call Crime Sorciere a Dark Guild too.

But I wonder what that makes Tartarus. Are they all bad people with Silver only being part of them for his own goals (Is anyone else reminded of the way Sieghart was part of Demon Card in RAVE?) or are they not really bad and only considered a Dark Guild because they ignore the laws, like Crime Sorciere?