Thesis Testimonial injustice is a failure of knowledge, not only a failure of fairness
Where it stands
I teach eleventh-grade English in Atlanta, and every year we read To Kill a Mockingbird. Every year a student asks why the jury did not believe Tom Robinson when the evidence was on his side. And every year I hand them Miranda Fricker, who uses that trial as a central example in Epistemic Injustice (2007).
Fricker's idea of testimonial injustice: a speaker receives less credibility than the evidence warrants because of prejudice about who they are. The usual reaction is to treat this as a moral wrong. It is unfair, it insults the speaker, it is racist. All true.
My thesis is that it is also, and distinctively, an epistemic failure. The jury in that novel did not just wrong Tom Robinson; it failed to know what happened when the knowledge was there for the taking. Prejudice cost the hearers truth. A community that systematically discounts some speakers believes less truth than it could, about precisely the things those speakers are best placed to know.
The Black feminist tradition said this long before the term existed. Anna Julia Cooper insisted in the 1890s that Black women had knowledge of their situation that no one else could supply; Patricia Hill Collins later wrote about who gets to validate knowledge claims. Du Bois's double consciousness is in part a theory of what the excluded can see.
The objection I expect: "the epistemic harm is just a side-effect of the moral one." I'd like to hear it argued properly.