Clearly, the "negro stable buck" is marginalized in Steinbeck's novella Of Mice and Men. Subject to the Jim Crow Laws. These laws followed the 1800-1866 "Black Codes," which greatly restricted the civil liberties of African Americans. They were yet segregated and in the old Confederate states restricted from owning property outside of cities; in addition, there were given only menial labor jobs. In essence, Crooks has no personal rights. For, when he tries to prohibit Lennie from entering his area, there really is little that he can do but complain. So, when he realizes that Lennie is mentally deficient, the literate and apparently rather clever Crooks toys with Lennie's feelings as a method of retribution for his treatment. Likewise, when Candy first arrives, Crooks reacts rather irritably because he feels that his individual space has been invaded.
Later, when Curley's wife steps foot into the barn, Crooks who has become somewhat emboldened by the friendliness shown him by Lennie and even Candy, tells the woman,
"Maybe you better go along to your own house now. We don't want no trouble."
But, he has overstepped his rights by speaking so to a white woman, and Curley's wife belittles him by calling him a pejorative name. After she does this, Crooks becomes fearful and "retired into the terrible protective dignity of the negro." However, when Candy further repels her, telling her to stop "messing aroun' with him [Lennie]," Crooks again bravely says,
"You got no rights comin' in a colored man's room. Now you jus' get out, and' get out quick. If you don't, I'm gonna ast the boss not to ever let you come in the barn no more."
However, Crooks regrets having said this because as a white person, Curley's wife has the advantage, "You know what I could do?" she asks pointedly. Defeated, Crooks "seemed to grow smaller" and he stands as close to the wall as he can and replies, "Yes, ma'am."
"Well, you keep your place then, N*****. I could get you strung up on a tree so easy it ain't even funny." After she says this, Crooks assumes the posture of a slave, head down, eyes averted from Curley's wife as his rights are only those given him by his boss.