Pansy wasn't on the good side lol. I don't have the book with me, but I think she was amongst the Slytherins in the Great Hall when Voldemort made his first sonorus speech demanding Harry be handed over. I think it was Pansy who stood up, pointed at Harry and said something like, "but he's right there. Lets hand him over." At which, all the Gryffindors stood up and pointed their wands at her..I think.