I found this article really interesting. It describes a legal case in which two chimpanzees, Leo and Hercules, were granted a writ of habeas corpus, and "implicitly ruled...[to be] legal persons." The two chimps had been held captive for experimentation at Stony Brook University. Though the final verdict hasn't yet been reached, I'm intrigued by the implications towards giving the chimpanzees a certain level of autonomy by giving them a habeas corpus which, by its definition (that a person cannot be illegally confined against their will), implies that the chimpanzees desires are being acknowledged.
The article also makes a point similar to both Bentham and Spiegel, where it compares the lacking rights of nonhuman animals to racism. It also agrees with Bentham's question of "can the suffer?" where it described the Nonhuman Rights Association's efforts to free the chimpanzees and their argument that they have "'the capacity to suffer pain of imprisonment,'" thus giving them a right to legal personhood. This article overall argues for the autonomy and personhood or nonhuman animals, with an emphasis on the legal system.