Well, her being a cop is self-evident, but let's review the entire comment:

She's a racist, classist noeliberal and a fucking cop (or close enough).

Her political career has been chock-full of attacking public institutions like schools, protecting white-collar crime which destroyed countless lives, protecting child molesters in the church, implementing policy against the poor, and protecting prison slavery. I'm not sure where exactly the confusion lies.

I would argue that, frankly, her being a neoliberal should be explained, for the sake of discussion, but her being racist and classist should be. The details of her career being "chock-full" of various acts should be coupled with specific citations to reporting of those acts. And so on.

I don't like Harris, mind, but the comment being discussed could have established its evidence in a more convincing manner.