Even in this day and age, employers continue to discrimination in hiring and in terms of employment based on an employee's race. This can be as mild as being more strict in imposing a discipline with employees of one race than with employees of other races, or Caucasian employees to demotions and termination. Some employers think that as long as they don't use racially offensive language, they will be able to cover up their discriminatory intent under the "at will employment" blanket and/or fabricating highly subjective reasons for terminating an employee, such as poor performance, insubordination, etc.  

Luckily, there is a whole body of law that the courts have developed over the years that provides guidance on using the inconsistencies / contradictions in the reasons given of employee's termination to prove or at least create and inference of racial or other kinds of discrimination against an employer. This is because the courts have found many years ago that when an employer provides reasons for employee's termination that are not true, the most likely reason for it is that the real reason for firing is illegal and/or discriminatory.  

Successful prosecution of a claim such as described above often requires intense discovery and careful analysis of the documents in both - the aggrieved employee's personnel file and in the employer's policies and internal communications.