Not in most states, especially if it is a right-to-work state. The employer can terminate your employment for any reason that is not specifically prohibited by law i.e. race, religion, sex, disability, etc.
Employers can sue employees in every state.
I believe you can sue both. Consult a lawyer.
You can sue them if they do, so essentially your answer is no. An employee cannot sue an employer EXCEPT when the employee already holds evidence that the employer violated a civil statute (EEO law, Workers COmp, unemployment, etc.). Without evidence that a civil statute was violated, no judge will allow you to file. Some statutes prohibit firing employees who report crimes in good faith, but the employee does not sue the government does.
When the employees believes that the reference provided by the employer was not true and resulted in defamation of the employee
When the employees believes that the reference provided by the employer was not true and resulted in defamation of the employee
No way. That agreement is nonenforceable even if you sign it. An employer may not preempt the right to sue, especially over an issue of illegal conduct by the employer. Agreements involving illegal behavior always nonbinding. However, the employer will most likely fire you if you sue them later, so be prepared to be unemployed. (Of course, you could then sue them again for unlawful termination). If a company is overtly concerned with this issue, you probably don't want to work there anyway.
It is illegal for an employer or manager to count and get waitress' tip money. If the employer or manager collects these, employee can sue employer for theft.
so that the employee doesn't have to sue the employer for medical benefits
Since Florida is a right to work state I don't think you can ever sue your employer.
You can sue, but unless you can demonstrate that you were harmed by this breach of confidentiality, it is not that serious a complaint.
Answering strictly on the fact stated in the question - - Unless there is a contractual offer or agreement to do so, probably not.
i pretty sure that the employer can sue...