1. (1) Except in a noncharter county of the first classification with more than one hundred fifty thousand and less than two hundred thousand inhabitants, the county sheriff in any county of the first or second classification shall receive an annual salary equal to eighty percent of the compensation of an associate circuit judge of the county.

(2) The county sheriff in any county of the third or fourth classification shall receive an annual salary computed as the following percentages of the compensation of an associate circuit judge of the county. If there is an increase in salary of less than ten thousand dollars, the increase shall take effect on January 1, 2022. If there is an increase of ten thousand dollars or more, the increase shall be paid over a period of five years in twenty percent increments per year. The assessed valuation factor shall be the amount thereof as shown for the year next preceding the computation. The provisions of this section shall not permit or require a reduction in the amount of compensation being paid for the office of sheriff from the prior year.

2. Two thousand dollars of the salary authorized in this section shall be payable to the sheriff only if the sheriff has completed at least twenty hours of classroom instruction each calendar year relating to the operations of the sheriff’s office when approved by a professional association of the county sheriffs of Missouri unless exempted from the training by the professional association. The professional association approving the program shall provide a certificate of completion to each sheriff who completes the training program and shall send a list of certified sheriffs to the treasurer of each county. Expenses incurred for attending the training session may be reimbursed to the county sheriff in the same manner as other expenses as may be appropriated for that purpose.

3. The county sheriff in any county other than a charter county shall not receive an annual compensation less than the compensation described under this section.