MO Rev Stat § 320.336 (2021)
2021 Missouri Revised Statutes|Title XXI - Public Safety and Morals|Chapter 320 - Fire Protection|Section 320.336 - Termination from employment prohibited, when — loss of pay permitted, when — written verification of service permitted — employer notification requirements.

Effective - 28 Aug 2008   320.336. Termination from employment prohibited, when — loss of pay permitted, when — written verification of service permitted — employer notification requirements. — 1. No public or private employer shall terminate an employee for joining any fire department or fire protection district, including but not limited to any municipal, volunteer, rural, or subscription fire department or organization or any volunteer fire protection association, as a volunteer firefighter, or the Missouri-1 Disaster Medical Assistance Team, Missouri Task Force One, or Urban Search and Rescue Team, or being activated to a national disaster response by the Federal Emergency Management Agency (FEMA).  2. No public or private employer shall terminate an employee who is a volunteer firefighter, a member of Missouri-1 Disaster Medical Assistance Team, Missouri Task Force One, or Urban Search and Rescue Team because the employee, when acting as a volunteer firefighter, or as a member of Missouri-1 Disaster Medical Assistance Team, Missouri Task Force One, Urban Search and Rescue Team, or FEMA is absent from or late to his or her employment in order to respond to an emergency before the time the employee is to report to his or her place of employment.  3. An employer may charge against the employee's regular pay any employment time lost by an employee who is a volunteer firefighter, or a member of Missouri-1 Disaster Medical Assistance Team, Missouri Task Force One, Urban Search and Rescue Team, or FEMA because of the employee's response to an emergency in the course of performing his or her duties as a volunteer firefighter, or a member of Missouri-1 Disaster Medical Assistance Team, Missouri Task Force One, Urban Search and Rescue Team, or FEMA.  4. In the case of an employee who is a volunteer firefighter, or a member of Missouri-1 Disaster Medical Assistance Team, Missouri Task Force One, Urban Search and Rescue Team, or FEMA and who loses time from his or her employment in order to respond to an emergency in the course of performing his or her duties as a volunteer firefighter, or a member of Missouri-1 Disaster Medical Assistance Team, Missouri Task Force One, Urban Search and Rescue Team, or FEMA, the employer has the right to request the employee to provide the employer with a written statement from the supervisor or acting supervisor of the volunteer fire department or the commander of Missouri-1 Disaster Medical Assistance Team or the FEMA supervisor stating that the employee responded to an emergency and stating the time and date of the emergency.  5. An employee who is a volunteer firefighter, or a member of Missouri-1 Disaster Medical Assistance Team, Missouri Task Force One, Urban Search and Rescue Team, or FEMA and who may be absent from or late to his or her employment in order to respond to an emergency in the course of performing his or her duties as a volunteer firefighter, or a member of Missouri-1 Disaster Medical Assistance Team, Missouri Task Force One, Urban Search and Rescue Team, or FEMA shall make a reasonable effort to notify his or her employer that he or she may be absent or late. ­­-------- (L. 2007 S.B. 47, A.L. 2008 H.B. 1883)