I think that Tessie can be seen as both a victim and as part of the problem in the town. She is reflective of the victimization practices of the town. Notice that her character is actually excited at the start of the short story. She is excited to be there, chatting with both Mr. Summers, and is shown to be an active member of the community. The opposition and voicing of unfairness that is present at the midpoint and end of the short story is not evident at the start of it. This beings to light how Tessie has little, if any, problem with the practices of the town unless she is impacted. It is at this point where I think Tessie's character gains a bit of depth. She has little problem with what is happening unless she is impacted and unless she is implicated. If someone other than Tessie pulled the piece of paper, it stands to reason that she would be like Mrs. Delacroix, searching for the biggest rock to throw. It is here where I think that Tessie's character can be seen as more than simply a victim. She is representative with the practices of victimization that are evident in the town, a collaborator who is devoured by the very system that she initially supports.
Passage 1: "Clean forgot what day it was," [Tessie] said to Mrs. Delacroix, who stood next to her, and they both laughed softly.
Passage 2: Mrs. Delacroix selected a stone so large she had to pick it up with both hands and turned to Mrs. Dunbar. "Come on," she said. "Hurry up."
In the first passage, Tessie and Mrs. Delacroix appear to be friends; they exchange pleasant words and laugh together. In the second passage, Mrs. Delacroix picks up a stone to throw at Tessie to kill her. The change in Mrs. Delacroix's behavior is surprising because there is no rational reason for it; Tessie hasn't done anything to merit Mrs. Delacroix's willingness to participate in her death.
It is likely that Tessie would have behaved the same way were Mrs. Delacroix and Tessie's positions reversed. Tessie, too, has participated in the lottery every year. There is no indication that she ever protested about the lottery's unfairness or brutality before. She only complains because, this year, she is chosen.
Having that said, though Tessie is a victim, she is not necessarily better than the rest of the villagers or particularly innocent. The fact that she has participated before, and would have again, allows Jackson to suggest that human beings' capacity for violence and brutality is something that is only limited when their personal well-being is threatened by it.