> that has hired 3 brazillians back to back

I've seen this kind of thing happen not through bias but because good people know good people, where by "good" I mean highly competent. They knew each other through university and other regional connections, so they happened to have the same ethnicity as one might expect from such a regional commonality. One got hired, referred another, and it cascaded. They were great to work with and highly competent, so I don't think there was bias even though it might appear that they're was.