why do black people have a black on black crime unit? but white people don't

why can balck rappers say on songs "crackers" "white motherfucker" and other racist stuff but its ok and they sell thousands of albums.

why on lethal weapon 4 does the black policeman say "please let the baby be black"

im not promoting/racism or whatever u may want to throw at me just voicing what i see/hear...

i honestly dont mean to offend no1