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RSMo 577.021effective 01 Jan 2017

Chemical testing authorized

In plain English

A certified police officer can give someone a chemical test (like a breathalyzer) before making an arrest if they think that person was driving drunk. If there was a crash where someone died or got seriously hurt, the officer is required to try to give that test. The test results can be used to show there was a good reason to arrest someone, or to help prove someone was not drunk, but the results cannot be used to show exactly how much alcohol was in their blood.

Word-for-word law

577.021. — reasonable efforts to test required — . — 1. Any state, county or who is chapter 590 may, prior to , a to any person suspected of operating a vehicle, , or aircraft or acting as a flight crew member of an aircraft while in an or with an .

2. Any state, county, or municipal law enforcement officer who is certified under chapter 590 shall make all reasonable efforts to administer a chemical test to any person suspected of operating a vehicle or vessel involved in a or accident which resulted in a or as defined in section 556.061.

3. A test administered pursuant to this section shall be of to arrest and as , but shall not be admissible as evidence of . The of sections 577.019 and 577.020 shall not apply to a test administered prior to arrest pursuant to this section.

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Source & history notes

(L. 1993 S.B. 167, A.L. 1996 H.B. 1169 & 1271 merged with S.B. 722, A.L. 2001 H.B. 302 & 38, A.L. 2006 S.B. 872, et al., A.L. 2014 S.B. 491) Effective 1-01-17 (2023) Numerical result of a preliminary breath test is admissible for the purpose of establishing probable cause, required to be proven by the director of revenue to suspend or revoke a driver's license under section 302.515. Wilmoth v. Director of Revenue, 669 S.W.3d 102 (Mo.banc).

View official source

Legal information, not legal advice. Always confirm with the official source at revisor.mo.gov.

RSMo 577.021: Chemical testing authorized | KnowMo Laws