i never really cared for her but the thing that made me hate her was the duke lacrosse team incident.
so the story was that a hand full of players on the duke lacrosse team was accused of raping a black girl (which is relevant because she filed for a hate crime on top of the rape charge).
she was convinced from day one that the duke lacrosse team was guilty. So when the victim had the "semen" tested to prove they did it, it turned out to be like egg or something. when this news was release nancy still was saying well "just because we can't prove they did it yet doesn't mean they didn't do it" and she call for them to be expelled and harassed. well eventually it turned out that the black girl made up the entire event and the reason was that she was turned down by one of the players and was just disgruntled.
the next day, nancy didn't even mention the story. no apology no acknowledgment. (also as a corollary this is why i have less respect for civil rights leaders because they did the same thing. they backed her immediately and never acknowledged that they made a mistake).