Thank you for that additional information. First of all, you need to understand that Texas is an "at will" employment state. At-will employment means that without a contract, you have no contractual or other right to employment with the company. The company is entitled to fire you for any reason: a good reason, a poor reason, or no reason at all--as long as the company does not fire you for an illegal reason (race, gender, age, religion, etc...). But it extends beyond firing, to hiring, promotions, demotions, wage cuts and raises, disciplinary actions, and even scheduling. Unless you can show that this was done in violation of a contract, union agreement, or a clear violation of an unambiguous and binding clause against the employer, or that it was done because of some minority status (age, race, gender, religion, disability) that you have, then they do have this discretion.
Now the fact that you were called this and he was making racially insensitive jokes indicates that there was a hostile work environment, which the management has a duty to take reasonable action to stop. You certainly can't be fired for complaining about this, so if that's the reason that you were fired, you'd have a case. But the first step in any employment litigation based on discrimination is the filing of the complaint with the EEOC. As it seems that you've done that, the ball is in their court. They will conduct an investigation, and either find that the complaint is meritorious or not. If so, then you'll get a "right to sue" letter, in which you can take it to an employment litigation attorney (if a settlement has not been reached) and then can take it to court. But if you don't get this letter, the odds of being successful in court are slim to none. That is, the EEOC standard of proof for determination as to whether discrimination occurred is LESS than what you would need to meet in court. So if they can't find enough evidence to give you the right to sue letter, then you probably wouldn't win in court.
Assuming that you do get a right to sue letter from the EEOC,you would need to contact an attorney in your area that deals with employment law / employment discrimination cases. Go to www.lawyers.com or www.legalmatch.com to find an attorney in your area. You should be able to find one that will give you a free initial consultation and better advise you of your rights, any problems with your case, likelihood of success, how courts are treating cases such as yours in your area, and what you should do next.
Hope that clears things up a bit. If you have any other questions, please let me know. If not, and you have not yet, please rate my answer AND press the "submit" button, if applicable.
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Thank you, ***** ***** luck to you!