Unless you have a contract (this may also be implied), have evidence that this termination was based on illegal discrimination (race, gender, age, so on), or this violated public policy (whistleblower), you have pretty much no chance of winning a wrongful termination lawsuit. As in every state but one, you are an employee at-will and you can be fired for any reason or not reason. The only way to know if you have a case at all is by retaining an employment lawyer so they can review all the facts.
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Mr. Murillo is absolutely correct. It has to be a violation of your contract, a union agreement, or you are being discriminated against for a Title VII reason - age, race, gender, ethnicity, etc. or disability, then you have no chance of winning a wrongful termination lawsuit. With CO being an at will state, a boss can fire you for wearing a Oakland Raider or Kansas City Chiefs polo if he is a huge Broncos fan.
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Employment Discrimination in the workplace Gender discrimination in the workplace Employment forms Employment contracts Employee rights Whistleblowing in the workplace Termination of employment Wrongful termination of employment Types of employment At-will employment Gender discrimination Discrimination