Maryland Code, Education § 23-802

(a) An employee who may effectively recommend an action listed in § 23-801(l) of this subtitle may be deemed a supervisory employee if the employee's exercise of the authority requires the exercise of independent judgment and is not merely of a routine or clerical nature.

(b) The exercise of any single function listed in § 23-801(l) of this subtitle may not necessarily require the conclusion that the individual exercising that function is in fact a supervisory employee within the meaning of the definition.

(c) In differentiating a supervisory employee from a nonsupervisory employee: