Five years after it approved destroying three glaciers to make room for a gold mine, Chile's environmental regulatory agency, Conama, reversed this decision and instead applied the precautionary principle to protect these glaciers. Although Conama's reversal was a response to public opposition and industry pressure, not new scientific information, every participant in this conflict invested heavily in science. This chapter explores why that was, and what role participants expected science to play in the negotiation over the glaciers? and the mine's future? Seen as a conflict over procedural and environmental injustices, the conflict over this mine, called Pascua Lama, exemplifies the uneven, tense and ultimately unproductive ways in which scientists have been enrolled as spokespersons for nature in Chile's emerging liberal democracy.