Performance Reviews are Generally Not Regulated By Law
Many workers don't realize that the performance reviews that they receive from their management and their content for the most part are not regulated by law. Employers have sound discretion in determining how to review their employees' performance, how often to do it, in what format, and whether or not to do it all. The content of performance reviews is also not subject to legal review. In other words, the fact that an employee believes that his/her performance review is unfair has very little, if any significant. The only way it can be used in a wrongful termination claims as additional, circumstantial evidence of otherwise discriminatory or retaliatory firing.
Employers have an unqualified right to use their subjective opinion in evaluating their employees' performance. The courts do not interfere in that process. Thus, if you have a dispute with your employer over the quality of your performance, you must remember that you are hardly helping yourself by simply getting defensive and disagreeing with your employer's opinion.
Receiving an unfavorable performance review can be a stressful and frustrating experience, especially when the employee tries his hardest to do the best job he can and truly believes that he does well. However, in the absence of evidence of unlawful discrimination or retaliation, the right way to address bad performance reviews is constructively - by both asking for the more specific feedback and criticism in your performance issues and by trying to improve at least some aspects of your work.