UK Borders Bill

I wonder what the employer’s code of conduct will say about a job applicant who is clearly from a racial minority—let us say he appears to be Somali. An employer knows he is under an obligation not to employ anyone who is here illegally. Is there not a temptation for him to safeguard his own back by saying to the applicant, ““Have you got a BID?””, or, ““What other evidence have you got to satisfy me that I am legally empowered to employ you?””?