Who sets the password?

[Aesha Malikah Takreem Williams]

No: HPFGUIDX 81530

    Liz (jade_sirocco) mentioned that in 2nd year, the Slytherin password was "pureblood". I wonder if this is an indication that the prefects set the password, because it seems like it would be improper for the word "pureblood" to be the password... and I highly doubt Dumbledore would choose it, and I think Snape might not, either (since he's not working for the Dark Lord anymore, does he harbor the same racist tendencies? Or did he just decide world domination, mass murder and torture weren't the ways to go about getting rid of "their kind"?) I mean, it seems to me that pureblood has at the very least a bad connotation... it seems to be the opposite of the word "mudblood", which we all know is a horrible thing to call someone. Then again, perhaps pureblood isn't used the same way that mudblood is. 
    But then I thought a prefect in one of the books said that McGonagall gave them the password. But perhaps I'm confusing that with Alicia's statement about McGonagall telling her she was captain. 

Aesha

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