They don't hire new people over 55, because they're a government agency built around the assumption that everyone will be there for forty years, and it's a bad

They don't hire new people over 55, because they're a government agency built around the assumption that everyone will be there for forty years, and it's a bad idea to have 95-year-old employees. 55 is also the usual age of retirement in the public sector. For existing workers, this and other government agencies are massively biased in favor of the old. Everything important - salary, benefits, job title, responsibility, prestige, etc. - is given out almost entirely by seniority. At least in the US, there's basically no one who matters in government under age 45.