the place i work is letting go an employee who is mentally handicapped he is a good person and worker i need to know if there are any laws that can protect his job
In the U.S.? Yes, there are laws that protect the disabled from being discriminated against in the workplace. According to the Federal Americans with Disabilities Act (1990), a disabled person cannot be fired, not hired, or given unequal working conditions due to disability.
Depends on why, of course, this person was fired. And your employer must have at least 15 employees to qualify. Or, to be protected by similar state law, 4 employees.
Good luck!