There is no law regulating this for private sector employers. Unless you are a union employee covered by a collective bargaining agreement or you have an employment contract specifying that you can only be terminated "for cause," your employment is "at-will." At-will employment means that an employer can terminate an employee for any reason or no reason at all, so long as no law is violated. The employer does not need to justify its actions, utilize progressive discipline, or allow the employee an opportunity to present his/her side of the story. In other words, you can be terminated for even a single missed day of work. Unless you have a record of disability, that is known to your employer, or you have taken a medical leave of absence, most likely there is no law prohibiting your employer from contacting your doctor. However, HIPAA laws would likely prevent your doctor from disclosing any health-related information to your employer without first obtaining a release from you.
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