"...Most federal employees have a sense that discrimination based on age is illegal. If that’s true, why do most law enforcement officers and firefighters have a mandatory retirement age, usually 57, and most air traffic controllers face mandatory retirement at age 56? Congress passed laws both prohibiting age discrimination for most federal employees and requiring mandatory retirement based on age for limited occupations.
A review of the rules is helpful to understand how these seemingly contradictory principles can co-exist..."