Russell Peters and “Brownface”
You might be aware of a rightfully maligned style of comedy known as Blackface.
According to Wikipedia..
Stereotyped blackface characters developed: buffoonish, lazy, superstitious, cowardly, and lascivious characters, who stole, lied pathologically, and mangled the English language. Early blackface minstrels were all male, so cross-dressing white men also played black women who were often portrayed either as unappealingly and grotesquely mannish; in the matronly, mammy mold; or highly sexually provocative. The 1830s American stage, where blackface first rose to prominence featured similarly comic stereotypes of the clever Yankee and the larger-than-life Frontiersman; the late 19th- and early 20th-century American and British stage where it last prospered featured many other, mostly ethnically-based, comic stereotypes: conniving, venal Jews; drunken brawling Irishmen with blarney at the ready; oily Italians; stodgy Germans; and gullible rural rubes.
So when does ethnicity based comedy crossover into “blackface” type material?
My answer is- when it dehumanizes a group rather than simply poke fun at them.
For example a comedian mocking jewish mothers for their obsession with academic success and guilt, does not cross the line as the subjects of his observation are still decent but somewhat flawed human beings. Similarly a comedian opining on the drinking habits of the Irish is not representing them as fundamentally subhuman beings.
Blackface type material is different because it is devoted to portraying the targeted group as subhuman, with no redeeming qualities. Using that criteria, it is my opinion that Russell Peters comedy acts IS “brownface”, though he tries to appear balanced by token offensiveness to other ethnic groups.