It's totally cool to send poors to poor farms, as long as all poors are treated equally.
Long jail sentences for possession of marijuana? Absolutely no injustice there, provided the law itself doesn't contain any clause targeting certain groups.
Abortion ban? Completely just, given that the law applies to all women.
I mean, no matter how invasive, pointless, or restrictive a law is, there can be zero injustice as long as it's applied fairly.