Hi,
There is nothing in the law that states that employers must behave and cannot be an absolute jerk, other than an employer must not discriminate (single out) someone or several persons due to their age, disability, national origin, pregnancy, race, religion, gender or other statuses protected by state or local law. Also, an employer may not retaliate against a person who is protecting his/her legal rights, such as filing a complaint of discrimination or filing a claim of workers compensation.
Thanks,
Kelly.