Source: https://www.joshgarrettlaw.com/blog/2017/february/boating-while-intoxicated-in-missouri/
Timestamp: 2019-04-23 14:33:05+00:00

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Southwest Missouri and Northwest Arkansas are home to several amazing lakes, Taneycomo, Bull Shoals, and Table Rock. As many people from throughout the nation as well as locals come through to enjoy these lakes, it is important to keep in mind that drinking and "driving" laws also apply to boating. The following piece was written by friend of Smith Law Firm, Nick Dudley, an accomplished criminal defense attorney in Blue Springs Missouri. Nick's blog is available at DudleyDefense.com.
Missourians are fortunate to have so many excellent lakes to enjoy. As Summer begins in full swing, people will enjoy a day on the water boating, skiing, tubing, grilling, and drinking. However, drinking and operating boats on Missouri waterways is fraught with legal peril.
Missouri has three laws that cover Boating While Intoxicated ("BWI"), and each one will affect water-goers differently.
The first and most common BWI law in Missouri is Operating a Vessel While Intoxicated. RSMo § 306.111.
"A person commits the crime of operating a vessel while intoxicated if he or she operates a vessel on the Mississippi River, Missouri River or the lakes of this state while in an intoxicated condition. Operating a vessel while intoxicated is a class B misdemeanor."
Vessel is defined as: "every motorboat and every description of motorized watercraft, and any watercraft more than twelve feet in length which is powered by sail alone or by a combination of sail and machinery, used or capable of being used as a means of transportation on water, but not any watercraft having as the only means of propulsion a paddle or oars"RSMo § 306.010.
And intoxicated is later defined by 306.111 as "a person is in an intoxicated condition when he or she is under the influence of alcohol, a controlled substance or drug, or any combination thereof."
This is a strange statute in many regards. The statute does not include the state's smaller rivers, any vessel powered by oars or paddles, or small sail/paddle boats. The law covers both alcohol and drugs, and is particularly unclear whether prescription drugs are covered. I think that this is the most common way to charge someone with BWI in Missouri because of the difficulties associated with getting a boat driver to a breathalyzer machine.
The next bwi charge is operating a vessel with excessive blood alcohol content. rsmo § 306.112.
"A person commits the crime of operating a vessel with excessive blood alcohol content if such person operates a vessel on the Mississippi River, Missouri River or the lakes of this state with eight-hundredths of one percent or more by weight of alcohol in such person's blood."
Like Operating a Vessel While Intoxicated, excessive BAC is also a class B misdemeanor.
This law is very similar to its motor vehicle counterpart (RSMo § 577.012). Additionally, there is a companion law that establishes presumptions. If a person blows .08 or above, it establishes prima facie evidence that a person is intoxicated. If a person blows between .05 and .08, no presumption is created. Finally, if a person blows below .05, he/she is presumed not-intoxicated. RSMo § 306.117. (This used to be the law for motor vehicles as well, but no longer).
Finally, Missouri criminalizes reckless or drunken operation or use of boats or skis. rsmo § 306.110.
"No person shall operate any motorboat or watercraft, or manipulate any water skis, surfboard or other waterborne device while intoxicated or under the influence of any narcotic drug, barbiturate or marijuana."
This statute is much different than the previous two. It is not limited to lakes or the Missouri/Mississippi Rivers, nor is it limited to "vessels." I don't know if anyone has ever been prosecuted in the state for operating a canoe while intoxicated under this law, but it seems possible.
Each of the BWI laws are B class misdemeanors for a first offense, but the punishments get progressively worse for multi-time offenders. Prior offenders (people with one BWI on their record from the last 5 years) are A misdemeanors. Persistent offenders (2 or more intoxication related boating offenses) are D felonies. Aggravated offenders (3 or more) are C felonies. Finally, Chronic offenders (4 or more) are B felonies. That means multiple offenders can be sentenced to up to 15 years in prison.

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