On the other hand, it bears mentioning that you can be racist in your choice of selection criteria, if you choose criteria based on their ability to produce a certain racial outcome.

The use of a poll tax people have to pay in order to vote isn't racist per se, but in the segregationist south, poll taxes were used as a mechanism to suppress black votes because they knew (disproportionately poor) black people would have a harder time paying it, and this use was racist.