This is Samuel and I will discuss this and provide you information in this regard.
Colorado does have an exception to the "at will" employment without a written contract and that is an implied contract.
Courts have found that an implied contract was formed in the following circumstances:
1 In trying to convince a prospective employee to take a job, an employer promises the employee that he will only be fired if he doesn't do his job well.
2 An employee manual states that once employees have completed an initial 90-day probation period, they become "permanent" employees.
3 During an evaluation, a supervisor gives an employee a glowing review and says that he will have a long future at the company as long as his good performance continues.
So yes, you could have an Implied Contract for Permanent employment. However, that does not mean that you cannot be terminated for "Good Cause." Some examples of good cause include poor job performance, low productivity, refusal to follow instructions, habitual tardiness, excessive absences from work, threats of violence, violating company rules, stealing or other criminal activity, dishonesty, endangering health and safety, revealing company trade secrets, harassing coworkers,
disrupting the work environment, preventing coworkers from doing their jobs, and insubordination.
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