MO Rev Stat § 70.820 (2021)
2021 Missouri Revised Statutes|Title VI - County, Township and Political Subdivision Government|Chapter 70 - Powers of Political Subdivisions to Cooperate or Contract with Governmental Units|Section 70.820 - Authority of peace officers to respond to emergencies outside jurisdiction — definitions — authority of certain peace officers — authority of federal law enforcement officers.

Effective - 28 Aug 1997   70.820. Authority of peace officers to respond to emergencies outside jurisdiction — definitions — authority of certain peace officers — authority of federal law enforcement officers. — 1. Any law enforcement officer as defined by section 556.061, full-time peace officer as defined by section 590.100, of a county or a full-time peace officer of any political subdivision who is certified pursuant to chapter 590, or a chief executive officer as defined by section 590.100, of a county or any political subdivision, certified pursuant to chapter 590 shall have the authority to respond to an emergency situation outside the boundaries of the political subdivision from which such peace officer's authority is derived. This section does not apply to any peace officer certified pursuant to subsection 6 of section 590.105.  2. Before a peace officer shall have the authority to respond to an emergency situation outside the boundaries of the political subdivision from which the officer's authority is derived pursuant to subsection 1 of this section, the authority shall be first authorized by ordinance, order, or other ruling by the governing body of the political subdivision from which the officer derives such officer's authority and by the governing body of the political subdivision in which the emergency situation is alleged to be occurring and by the board of police established by section 84.020 or by the board of police commissioners established by section 84.350 if the officer derives his authority from either board or if the emergency situation is alleged to be occurring within the jurisdiction of either board.  3. As used in this section, "emergency situation" means any situation in which the law enforcement officer has a reasonable belief that a crime is about to be committed, is being committed, or has been committed involving injury or threat of injury to any person, property, or governmental interest and such officer's response is reasonably necessary to prevent or end such emergency situation or mitigate the likelihood of injury involved in such emergency situation. The determination of the existence of any emergency situation shall be in the discretion of the officer making the response or in the discretion of an officer or governmental officer of the political subdivision in which the emergency situation is alleged to be occurring.  4. As used in this section, "response" shall mean to take any and all action which the officer may lawfully take as if exercising his powers within his own jurisdiction.  5. In addition to the emergency response powers prescribed in subsection 1 of this section, any peace officer of a county of the first classification with a charter form of government, or any peace officer of any political subdivision within any county of the first classification with a charter form of government, or any peace officer of any city not within a county, who has completed the basic peace training program pursuant to chapter 590 may arrest persons who violate any provision of state law within the boundaries of any county of the first classification or of any city not within a county.  6. In addition to the powers prescribed in subsections 1 and 5 of this section, section 544.216, and any other arrest powers, a law enforcement officer or federal law enforcement officer as defined in subsection 8 of this section, may arrest on view, and without a warrant, at any place within this state, any person the officer sees asserting physical force or using forcible compulsion for the purpose of causing or creating a substantial risk of death or serious physical injury to any person or any person the officer sees committing a dangerous felony as defined in section 556.061. Any such action shall be deemed to be within the scope of the officer's employment.  7. To provide assistance to law enforcement officers, a federal law enforcement officer shall have the same authority as a law enforcement officer where:  (1) The federal law enforcement officer is rendering assistance at the request of any law enforcement officer of this state; or  (2) The federal law enforcement officer is effecting an arrest or providing assistance as part of a bona fide task force or joint investigation in which law enforcement officers of this state are participating.  8. A federal law enforcement officer is a person employed by the United States government who is empowered to effect an arrest with or without a warrant for violation of the United States Code and who is authorized to carry a firearm in the performance of the person's official duties as a federal law enforcement officer and includes a law enforcement officer as defined in section 556.061. ­­-------- (L. 1986 S.B. 450 § 19, A.L. 1987 S.B. 372, A.L. 1994 S.B. 475, A.L. 1997 H.B. 69 & 179 & H.B. 669)  CROSS REFERENCE:  Arrest powers, peace officers and conservation agents, 252.085