Promotions shall be based on merit to be ascertained by examinations to be prescribed by the sheriff and the commission. All questions relative to promotions shall be practical in character and such as will fairly test the merit and fitness of persons seeking promotion. The sheriff of the county shall have the discretion to promote the person or persons of his choice from the list of those who have successfully completed the appropriate examination and are certified as eligible for promotion by the commission.
The sheriff of the county shall have the power to determine whether an increase in salary shall constitute a promotion.
16 P.S. § 4221.8