In boating while intoxicated cases the motto must be "Just say no, don't blow!"
There is no reason to submit to any testing in a boating while intoxicated case. One does not lose their motor vehicle driving privileges for refusing testing in a boating while intoxicated case so the benefits of denying the State potential evidence to use against the individual to obtain a criminal conviction for boating while intoxicated greatly outweigh the benefit to taking the tests.
If a person refuses the evidentiary breath test at the station in a boating while intoxicated case, the individual obviously can still be charged with the criminal offense under the theory of being "under the influence" of alcohol, however, the State's case is much weaker without any "tests" then it is with a "test" result. The only consequence in addition to the potential criminal charge which would be filed if the person took and failed the test anyway, is a $500 civil penalty (for a first offense) and an order prohibiting the individual from operating a motorboat or sailboat for a year. Most people can live with not driving a boat for a year, especially in Iowa where the boating season is maybe 4-5 months long. That being the case, there simply is no reason to voluntarily provide the government with evidence necessary to prosecute and obtain a criminal conviction for the offense of boating while intoxicated?
Furthermore, there are significant constitutional issues and challenges that can be made when the State attempts to impose punishment and "civil penalties" against an individual in a boating while intoxicated case for refusing to submit to testing. Every individual in the United States of America has the constitutional right to elect not to consent to the search of their person, place or effects. In motor vehicle operating while intoxicated cases, the United States Supreme Court and Iowa Supreme Court have adopted and approved the legal doctrine of "implied consent" which in essence states that by obtaining a drivers license and driving on public highways built for the public's use and enjoyment, all drivers of motor vehicles "impliedly consent" to testing their bodily fluids for drug or alcohol concentration if suspected for operating while intoxicated. This is called "implied consent" which permits the State to use coercion by threatening drivers license suspensions against the person to obtain their consent to chemical testing. Additionally, pursuant to the doctrine of "implied consent", if a person refuses to submit to testing, the State is authorized to impose a punishment against the individual as opposed to forcibly extracting their bodily fluids for chemical testing.
The problem that arises in boating while intoxicated cases is that no driver's licenses or permits are required to operate a motorboat or sailboat in the State of Iowa. Additionally, the waterways are natural as opposed to constructed roadways built and paid for by the State and Federal governments. As a result, the fundamental principals upon which the doctrine of "implied consent" rest, do not apply in boating while intoxicated cases. Thus, the argument goes that the State is not justified in obtaining one's consent to chemical testing through the use of coercion and the State cannot punish the individual for exercising a constitutional right to refuse consent to the search of their person.
Ultimately, these issues are now before the Iowa Supreme Court on an appeal being handled by GRL Law. However, until a decision is reached in that case the motto in boating while intoxicated cases continues to be "Just say no, don't blow!"