>"X is in a category whose archetypal member gives us a certain emotional reaction. Therefore, we should apply that emotional reaction to X, even though it is not a central category member."

The difference between calling MLK a minister and calling him a criminal is that being a minister isn't as negative. Nonetheless, calling him only a minister does evoke an emotional reaction that doesn't quite capture the power of MLK's role in society. Introducing him as a minister is an example of the non-central fallacy, but it's played for ironic effect.