Newly turned, unwillingly. Killed her sire and didn't dispose of the body properly. One of the older vampires - a Carmilla? - was willing to vouch for her, with the understanding that both of them would be punished for any future missteps.

[ He shakes his head, not that Alucard's in a position to see it. ]

This one is- fifteen years since turning, I think? Old enough to know better. And I doubt there'll be anyone willing to vouch for him.