Provided the candidate is in shape, retired from the Air Force honorably as an F-16 Aircraft Maintenance crew chief, still has a valid security (Secret) clearance, never did drugs or was convicted of a crime*, can that person be a police officer/state trooper even at age 39?
*Florida License was revoked for a year at age 25 for excessive points due to speeding tickets (always paid - never went to warrant) but clean driving record since then.