Most employee-employer relationships at "at will." That is to say, once an employee is hired, he reserves the right to give his workers employment for as long as he finds in necessary. At any point, he may terminate the employment arrangement for any reason he wishes. One exception to this is when it can be proven that an employer has discriminated against an employee, then relieved them of their duties. According to federal law, employees may sue for wrongful termination if they can prove discrimination based upon their, race, age, ethnicity, or religion. Some states have additional anti-discrimination statutes. An "at will" employee contract is almost always unwritten, and thus is to be governed by applicable local, state, and federal laws.