Employment law is a constantly changing field. Developments in the law reflect a constant tug-of-war between the notion that people should be free to make any agreements they wish, and the understanding that employers have so much economic power that employees need some protection. For most people, employment at will means that employment can be ended at any time, and employees are entitled to pay for their hours worked, plus vested employment benefits.
Federal and state law have altered this relationship in some areas. Employment actions, including harassment, are illegal if they are taken because someone is a certain race, gender, religion, national origin,age, or disabled. Most jobs are subject to a minimum wage, and unless exempt, overtime must be paid for hours exceeding 40 hours per week. Employers cannot take measures designed to prevent employees from communicating among themselves about their working conditions.
Despite the length of the list of protections, most people who are fired for an "unfair" reason, or because someone lied about their actions have no recourse, other than unemployment compensation. It is highly unlikely that Congress or the Maryland General Assembly will require employers to have just cause for firing, and unless a union or individual contract requires good cause, employment at will rules out lawsuits for unjust firings.