Rivers was considered controversial by PETA for owning and wearing fur. She responded openly and frankly to criticism, telling protestors in one instance that the furs she was wearing which "would have been lying in a cellar" had now "gotten to go to the opera." Rivers added that she agreed with the organization's message. "I have four rescue animals, so we all do what we do in our own way."
Following her death, PETA's senior vice president Dan Mathews published a statement on The Huffington Post which lauded River's compassion for animals. "Despite her penchant for wearing fur, Joan always appreciated PETA's efforts," stated Mathews. "We'll all miss Joan terribly, but her legacy will live on in many meaningful ways."
Rivers also supported such causes as Guide Dogs of America and Lucy Pet Foundation.