The modern animal advocacy movement, as well as its countermovement mobilisations, frequently (and correctly) presents the book Animal Liberation as the origins of second wave animal advocacy (assuming acceptance that the efforts of Henry Salt’s Humanitarian League amounts to the "first wave"), along with an implicit and often explicit (and incorrect) claim that the book, and therefore the movement, is based on Peter Singer’s (nonexistent) "animal rights perspective."
The frequent characterisation of his utilitarian perspective as an animal rights position, and presumably the number of times Animal Liberation has been described as "the animal rights bible," has seemingly led its author to regret ever having used rights language, even rhetorically and, according to Regan, Singer remains committed to his claim that attributing rights to other animals is not possible.
Some of the misrepresentation of Singer’s work as rights-based theorising, especially by pro-use countermovements, appears on the face of it to be deliberately ideological in intent. However, in relation to what Singer says about his own position, Gary Francione fully accepts that Singer is entirely consistent to the extent that he rejects the notion of moral right holding in the case of human and nonhuman animals. Moreover, his consistent utilitarian principles have led Singer to accept that "there might be circumstances" in which human and animal exploitation…could be justified in light of consequences.
Francione suggests, however, that rights concepts are always likely to be important and invoked as resources in human affairs and, therefore, utilitarian "balancing" of human and nonhuman interests are extremely dangerous in terms of nonhuman interests. Dangerous precisely because protective rights considerations are not conceptually available "to limit the results of the balancing process." Francione clarifies the point by putting it in a different way, while at the same time revealing how authentic animal rights theorists attempt to build on already established ways of thinking about the protection afforded by bearing rights:
- the utilitarian notion of “consequences” cannot be interpreted in a way that does not prejudice the issue of animal protection. Even if we do accept that animals have interests, it is simply difficult to make determinations of those interests from a humanocentric perspective; it is because we systematically devalue and underestimate the interests of disempowered populations that rights concepts are necessary in the first place. Although rights theory rests ultimately upon a consideration of animal interests, rights theory does not permit the sacrifice of animal interests simply because human interests would be served. Rather, rights theory assumes that at least some animal interests are entitled to prima facie protection and that the sacrifice of those interests require a justification not dissimilar to that required when we seek to override human interests protected by rights.
The questions, "where do rights come from?" and "how are 'rights' used in animal rights thinking?" are, of course, pertinent. Perhaps the first thing to be said about matters concerning any formulation of rights, following Steve Kangas, is that "the origin of rights is a messy and complex debate." Kangas suggests that the understanding of the first question of where rights "come from" can be aided by separating out three types of thinking about rights: conservative, liberal, and libertarian, and also by thinking about four initial bases put forward for the creation of rights: that rights are "natural" (following Locke), "inalienable," "God-given," and "self-evident."
Kangas states that until a few hundred years ago, most philosophers believed that rights could be defined in these four ways. However, "today, most philosophers agree that rights are social constructs, open to change." He says that this view accords well with the "liberal" stance, since, "Liberals believe that rights are social constructions, defended by force and open to change and improvement." Kangas is almost certainly correct to state that rights cannot be regarded as self-evident because, as he notes, "philosophers have been vigorously arguing about them for thousands of years."
It is not difficult to find support for Kangas’ assertion that debates about rights can be messy and complex. For example, Carl Cohen, in his 1986 article, "Why Animals Have No Rights," states that "The differing targets, contents, and sources of rights, and their inevitable conflict, together weave a tangled web." Cohen’s title itself indicates philosophical controversy over recent rights claims. He has published a number of works addressing human rights concepts and the whole idea of nonhumans being right holders.
Whereas theorists such as Cohen argue that nonhuman animals, as a matter of logic, cannot ever be said to bear rights, Regan and Francione disagree and have put forward differing ways by which they argue that rights formulations can and should protect sentient nonhuman interests. While Regan’s position has been described as a liberal rights perspective, Regan characterise Cohen, like Singer, as a utilitarian theorist, at least "when reasoning in support of continued widespread and possible expanded reliance on nonhuman animals in biomedical research."  The difference between Cohen and Singer is that Singer argues that no animal, human or nonhuman, can hold rights, while Cohen argues that all humans do and nonhumans do not.
Tom Regan claims to adhere seriously to a commitment to develop an "informed, thoughtful moral outlook." According to Benton and Redfearn, strength within Regan’s strategy accrues from the "benefit of latching on to the currently near-universal moral priority attached to human rights." Although it may be rather unkind of them to label Regan’s approach "a strategy," as if his commitment to human rights was only for the following reason, Benton and Redfearn acknowledge that, "Regan was the first theorist to ‘get ‘rights’ across the species barrier."
Therefore, Regan can be credited with breaching that hitherto solid defensive ethical barrier based exclusively on species membership, of which the construction, maintenance, and usage of has featured prominently in some of my other blog entries.
 Adam Kydd’s on-line review (http://www.animalaid.org.uk/) of Francione’s Introduction to Animal Rights argues thatthis book should be seen ‘as the true bible of the Animal Rights Movement’.
 Regan, T. (2001) Defending Animal Rights. Urbana & Chicago: University of Illinois Press; Throughout Animal Liberation Singer is careful to talk about the "Animal Liberation movement" and never speaks of a clash between human and nonhuman rights, rather human and animal interests. In the 2nd edition of Animal Liberation, Singer was motivated to say something about rights formulations: "The language of rights is a convenient political shorthand. It is even more valuable in the era of thirty-second TVA news clips" (Singer, cited by Francione 1996: 49, 240). Francione, G. L. (1996) Rain Without Thunder: The Ideology of the Animal Rights Movement. Philadelphia: Temple University Press.
 Francione, G.L. (1995) Animals, Property, and the Law. Philadelphia: Temple University Press.
 www.huppi.com/ kangaroo/L-rights.htm
 Originally printed in the New England Journal of Medicine, Vol 315(14) (October 2, 1986): 865-69, this citation is taken from wysiwyg://19/http://www.responsiblewildlife management.org/carl_cohen.htm Critics of Cohen (including Regan [fn 2] and Nathan Nobis [http://courses.ats.rochester.edu/ nobis/papers.cohen-kind.html]) have noted how rare it is for a philosophical work to feature as the lead article in a medical journal.
 Benton and Redfearn write: "Peter Singer’s Animal Liberation is…within the utilitarian tradition, and it may be that the animal welfare movement’s concern with animal suffering is a measure of the pervasiveness of utilitarianism as the ‘common sense’ of secular morality." Benton, T. & Redfearn, S. (1996) "The Politics of Animal Rights - Where is the Left?" New Left Review, Jan/Feb: 43-58.