James O'Brien has said he feels 'like a mug' for defending the Cambridge University professor accused of plagiarism and fabrication. But Mr O'Brien also said he did not 'feel guilt' and suggested that only a racist would have doubted Mr Arday's credibility as a Cambridge professor of sociology of education. Since Mr Arday's resignation it has emerged he claimed to have locked-in syndrome and testicular cancer in a book proposal for his memoir. Mr Arday had initially faced allegations he had plagiarised tracts of his PhD thesis from research by another student. Universities including Glasgow, Durham and Ohio State in the US also rebuffed Mr Arday's claims to have held academic positions within their institutions.