In the U.S. there are many laws on the books to protect animals from abuse. But a group of lawyers is trying to take animal rights a huge step further. Led by longtime animal advocate Steven Wise, the Nonhuman Rights Project filed a lawsuit recently on behalf of a chimpanzee named Tommy. Citing evidence of the cognitive sophistication of chimps and other species, the group ultimately seeks personhood status for animals. A number of leading primatologists are among those who support the effort. But there is also enormous opposition – on legal, moral and practical grounds. Diane and her guests discuss the fight for legal rights for animals.