MacKinnon's work largely focuses on the difference between quality of social and economic conditions for women in both the private and public spheres of life. MacKinnon believes that society fails to recognize the existing hierarchies present within it that have subordinated women in particular for such a long time that they have been perceived as natural. “Men's forms of dominance over women have been accomplished socially as well as economically, prior to the operation of law, without express state acts, often in intimate contexts, as everyday life” (Mackinnon, 161).
MacKinnon writes about the interrelations between theory and practice, recognizing that women's experiences have, for the most part, been ignored in both arenas. Furthermore, she uses Marxism to critique certain points in feminist theory and uses feminism to criticize Marxist theory. She sees hypocrisy in much of Marx's theory due to his failure to mention women's oppression in relation to class oppression. MacKinnon notes Marx's criticism of theory that treated class division as a spontaneous event that occurred naturally. Marx saw class as an unnatural status quo resulting from the ownership of the means of production while at the same time thinking of women's responsibility for child-rearing as a "natural" sex role. She understands epistemology as theories of knowing and politics as theories of power. She explains, "Having power means, among other things, that when someone says, 'this is how it is', it is taken as being that way. . . . Powerlessness means that when you say 'this is how it is,' it is not taken as being that way. This makes articulating silence, perceiving the presence of absence, believing those who have been socially stripped of credibility, critically contextualizing what passes for simple fact, necessary to the epistemology of a politics of the powerless."
In 1996, Fred Shapiro calculated that "Feminism, Marxism, Method, and the State: Toward Feminist Jurisprudence", 8 Signs 635 (1983), was the 96th most cited article in law reviews even though it was published in a non-legal journal.