Kwame Anthony Appiah has an op-ed in Sunday’s New York Times dissecting the “as a” locution, in which one first announces one’s gender, race, sexual orientation, or class position before making an argument during a public discussion. He interprets it as a claim to represent the entire group defined in the preparatory clause, and explains why this claim is invalid; better you should begin with “speaking for myself”. But I disagree with his interpretation of what “as a” means; I think it communicates speaking from rather than speaking for.
From my experience, “as a” is an acknowledgment that one’s view of the world is limited by one’s background and identity. It’s a way to anticipate the criticism that what is being said is not universal or “true” in some objective but unattainable sense. Of course, that limitation can be valorized in different ways. If an oppressed identity is being invoked—or even better, an intersectionality of multiple oppressed identities—the partiality of perspective is even a strength, because it brings to the fore experiences and ideas that have historically been marginalized. By the same token, if one is speaking “as a” member of a dominant identity, the limitations are pernicious because they reinforce what has been unfairly imposed over the same long duration.
From an epistemological perspective, the immediate problem is that the “as a” formulation conflates two different consequences of the speaker being positioned in the world rather than above or outside it. One has to do with differences of experience, the other with proclivity to believe.