Persons claiming eligibility for disabled veterans preference must submit to the employment office, on or before the application deadline date, a certification from the United States Veterans Administration or a military service department, dated within 1 year, which certifies the present existence of a service related disability of 10% or more, or other acceptable proof of such disability as a result of his/her military service. Associate's degree in criminal justice, law enforcement, public/business administration, construction, planning, or other closely related field, or 60 semester (90 quarter) or more units with a minimum of 18 semester, (26 quarter) units in criminal justice; law enforcement; public/business administration, construction; planning; or other closely related field.