BUI boating under the influence

What Is BUI?

BUI is boating under the influence of alcohol or drugs. It’s illegal in Massachusetts and a BUI charge is just as serious as a DUI. More importantly, the law states that any watercraft vessel applies to the restriction.

This means you can get a BUI or DUI in a kayak, canoe, sailboat, motorized boat or any other watercraft if you are found guilty of being under the influence while operating the vessel.


The laws in Massachusetts treat boating under the influence similarly to driving under the influence. But there are some key differences that are important, especially from a defense standpoint. Read on to discover special differences between BUI vs DUI.

Reasonable Suspicion is the normal requirement for law enforcement to legally stop a motorist. That’s because the Fourth Amendment prohibits police from randomly seizing and searching citizens.

Many DUI investigations begin when police suspect or observe some other traffic violation, such as a tail light being out. But on the waterways, Massachusetts laws mandate that all boaters be subjected to “safety inspections” by boat patrol officers upon request.

So, while there are considerably fewer patrol boats on water than cruisers on land, you could easily be ensnared in a BUI investigation as officers board your vessel under a safety inspection pretext.

Related Q&A: Can you have alcohol or beer on a boat? There are few open container laws for boating in MA. However, my answer, given mandatory at-will inspections, is that you don’t risk having alcohol on board – even though the operator won’t be drinking.

Probable Cause If Massachusetts Environmental Police (MEP) board your boat for inspection or suspicion, they’ll need to develop probable cause before arresting you for being under the influence. The smell or sight of alcohol is usually the decisive factor, but officers know ‘odor’ isn’t enough for an arrest.

On roadways, probable cause for DUI can start with standardized Field Sobriety Tests (FSTs). Drivers are asked to exit the vehicle and perform a battery of physical tests such as the Walk-And-Turn, One-Leg Stand and Horizontal Gaze Nystagmus (the eye test).

Police are trained to look for certain struggles with the tasks that supposedly indicate impairment. FSTs are not mandatory under the law, and it’s best to politely refuse them.

However, on a boat in confined space where officers are already aboard your property, it’s very difficult to decline FSTs under police pressure to do so.

Standardized Field Sobriety Tests used on water for BUI are quite different than those used for a vehicle DUI investigation.

Many of us in DUI defense have successfully argued that performing FSTs after being on the water several hours puts the suspect at an enormous disadvantage. Constant water motion affects your sense of balance!

Enter Seated Field Sobriety Tests – marine enforcement’s solution to the equilibrium problem caused by being on the water for hours at a time.

You’ll be asked to perform tests while seated on your boat. The seated tests are: Finger-To-Nose, Palm Pat, Hand Coordination and HGN –the eye test. For a visual overview of these tests, watch this video.

Remember, the whole point of these tests —whether on land or water, is to develop probable cause for a BUI or DUI arrest.

Once your scores indicate you failed the seated FSTs, officers will arrest you for BUI and take you to the booking station. There, you’ll be given the choice of taking or refusing the chemical BAC test, known as the breathalyzer.

Refusing this chemical test will have negative consequences as your driver’s license will be automatically suspended; and your boating registration might also be revoked for a similar period of time. The legal BAC limit on a boat is the same for driving vehicles: 0.08

Related Q&A: Can you drive a boat with a suspended license? In Massachusetts, there’s no law mandating your boating privileges be simultaneously suspended with your driving privileges for moving violations. However, revoking your boater’s reg (your boating license) is very likely if you refuse the blood-alcohol test for BUI. Under the law, you can’t drive your boat without it.

Related Q&A: Does boating under the influence go on your driving record? Yes. If you are convicted of BUI, the commonwealth considers it a “like violation” under DUI laws. If you’re charged with another BUI, prosecutors can look back 10 years on your driver’s record for any prior BUIs.

Priors will be used to enhance your penalties as a multiple offender (if convicted of the new offense.)

If you are arrested for boating under the influence, you should consult with a DUI / BUI defense attorney with successful experience challenging field sobriety tests in court who is ready to challenge the seated sobriety tests. Read my case results here.

An attorney with the same official training for administering FSTs as officers can also dispute the accuracy of the results by revealing all testing and evaluation mistakes made.