The tagline "Is it because I's black" was used by a tagline of a white Oxford-educated Jewish comedian, Sacha Baron Cohen, who also was the creative force behind a truly appalling film starring a character called "Borat" (in which he used a racial stereotype character to mock what he saw as unworthy Americana)

This tagline was a catchphrase of his first famous funny character (I had to say that deadpan) called "Ali G". The "humour" lay in the fact that said comedian tried to dress and behave like a stereotypical street gangsta. Its apologists called it "post ironic". It always struck me as beneath contempt. The white Jewish comedian used the phrase (in character) whenever criticised.

While he was happy to mock the beliefs of others, he was once seen to throw a huge wobbler in the Ivy when he found bacon in the mashed potato. He was, it seemed, happy to demand that others respected his racial and religious beliefs while taking the piss out of everyone else.