
TheWarriorPoet519 |

I would imagine they're not terribly picky race-wise. So long as the character has the stalwart devotion to Order and Law and the fortitude to stay the course, as well as the strength of body to handle the job, they'll accept them.
They're probably more inclined to be skeptical of races that are known to be inclined more towards Chaos (I imagine they'd be leery of elves, for example), but if the individual can prove they have the chops, they'll take them.

RuyanVe |

There's a centaur on the cover of this book by Paizo - probably the female centaur, golem101 hinted at.
Ruyan.

Icyshadow |

Racism (and specieism) is detrimental to the law and order that the Hellknights seek to uphold, and I'm pretty sure even Lawful Evil ones who openly display their racism will be met with scorn by their peers and superiors, especially if said superiors are of a differing race. The law makes no exceptions when it comes to most things, and it doesn't care whether you're a lesser or a greater being, because in the end, all are equal when they face judgement. Though the Hellknights might judge a Tiefling by their origin, they most likely would not stop a promising candidate from joining them. Same goes for most other races, I'd presume.