"Deputy U.S. Marshals are eligible for retirement after 25 years of service or at 50 years old, with 20 years of service. The mandatory retirement age is 57. Military experience may increase years for retirement, but cannot be substituted for 20 years of law enforcement experience."

URL: www.usmarshals.gov/.../compensation.html

The United States Marshals Service (USMS) is a U.S. federal law enforcement agency within the U.S. Department of Justice (see 28 U.S.C. ยง 561). ===========================================================================================================