Theres this answer from Vince Nobile who I think makes the point:
"Are whites able to teach African American history? I know of no rational argument that proves that they are not. In fact, to make such an argument guts a vital part of our discipline: vicarious knowledge of the past. If whites are unable to teach African American history, they should not be able to teach the history of Latinos or Asian Americans, among others; then it would follow that a non-veteran is unable to teach war, an African American is unable to teach African history, a gentile is unable to teach the Holocaust, and so on. To be sure, individuals of a particular race, class, gender, or experiential background might offer special insights—the perspective of the oppressed, perhaps—or have an intuitive feel for the material, but there is very little else that is theoretically beyond the reach of the committed scholar. No, the notion that we must have some certified or symbolic membership card for the fields we teach is itself anti-history and need not detain us."