Another way people reveal their prejudice is by talking down to others - e.g. Hillary Clinton's famous schoolmarm way of speaking - especially if they do so repeatedly.
So, researchers in academia (Yale) were understandably surprised when the data revealed who does this, and to whom they do it.
Even more surprising... who doesn't do it.
The researchers found that liberal individuals were less likely to use words that would make them appear highly competent when the person they were addressing was presumed to be black rather than white. No significant differences were seen in the word selection of conservatives based on the presumed race of their partner. “It was kind of an unpleasant surprise to see this subtle but persistent effect,” Dupree says. “Even if it’s ultimately well-intentioned, it could be seen as patronizing.”