From a benefit's website. Actual title redacted to try to stay anon. I'm not the fed, my husband is.
[X jobs] are classified as law enforcement, or hazardous duty, and as such are required to pay a slightly higher portion of salary toward their retirement than non-hazardous duty employees (1.7% for law enforcement officers versus 1.2% for non-law enforcement employees in 2000). Under the Federal Employees Retirement System (FERS), Federal law enforcement officers may retire at age 50 with 20 years of hazardous duty service, or at any age with 25 years of hazardous duty service. Mandatory retirement age is 57 years old, as mandated under the provisions of 5 U.S.C. § 8335(b),8425(b).
I mistakenly thought retirement was mandatory at age 50 or 25 years of service. It is only mandatory at 57 apparently.