I don’t believe it does either. After going thru the academy, if a police force sets a 21 year requirement, thats fine. I don’t see much difference between 20 and 21 though. The 20 I think happens because some go to a 2 year criminal justice program at a JR. College when they get out of high school.
The 8th of November is comin’ up soon,,,
“19 and Green With A New M-16” comes to mind...