105 ILCS 5/10-20.7
To appoint all teachers and fix the amount of their salaries, subject to limitations set forth in this Act. In fixing salaries of certificated employees, school boards shall make no discrimination on account of sex and there shall be no loss in salary because of jury duty or because such employee, pursuant to subpoena issued by the clerk of a court and served on such employee, attends as a witness upon trial or to have his or her deposition taken in any school related matter pending in court, except that the board may make a deduction equal to the amount received for such jury duty or for per diem fees which the employee is entitled to receive for complying with such subpoena. Certified employees may be paid full salary by the board when in the active service of this State, under orders of the Commander-in-Chief, as members of the Illinois National Guard or Illinois Naval Militia, provided that the board may deduct from such salary any amounts received for such State service. A school board may at any time after January 1 employ teachers for the school year beginning on the following July 1.
105 ILCS 5/10-20.7