RedactedNarrative: INITIAL REPORT/NOTIFICATION 
  While on assignment at a boating safety checkpoint in the marina, I overheard an engine rev for a short time nearby and some indistinguishable comments/commotion immediately following. I looked over in time to see VESSEL #1 reversing rapidly and a man on the bow holding and looking at his R. arm. This occurred next to the BU slip dock just west of my location. I was then waved/called over by a slip renter on that slip dock with him also pointing toward the man apparently injured in the incident the bow of VESSEL #1. The initial report from the witness was that the individual on the bow of the boat may have broken his arm. I called our patrol vessel over and had subject transport me to the incident location on the BU dock. 
  
  ON SCENE 
  VESSEL #1 had temporarily parked in an empty slip nearby and a bystander offered a towel to wrap the arm with to stop apparent significant bleeding. The injured individual agreed to have medical respond so I had dispatch call the ambulance out. A witness said he observed what looked like the man on the bow of the boat trying to catch the boat on the slip dock finger with his arm caught in between the boat and dock as the boat lunged forward. VICTIM suspected his R. arm may be broken as well as a tear/laceration. While on scene, park staffer assisted with bandaging the injury with medical supplies from the patrol boat and I gathered incident information. 
  
  INCIDENT/INVESTIGATION 
  The operator said the throttle was not working correctly causing the boat to lunge forward unexpectedly as they were waiting to load the boat. He showed me how the throttle was spinning around the base as if not catching gears or with a slipping cable. I checked for the presence of alcohol and found nothing. OPERATOR stated he had nothing alcoholic to drink and other occupants said there was no alcohol on the boat. OPERATOR also provided me with a completed witness statement which will be attached to this report. 
  In looking at the area of impact on the dock, it appeared that the bow of VESSEL #1 struck the dock finger as well as a dock cleat. It appeared the cleat of the dock caused minor damage to the fiberglass on VESSEL #1. It is unknown if VICTIM's arm was caught against the dock itself or the cleat. No blood was visible on the cleat or dock. Pictures were taken of the damage on VESSEL #1 and the nearby slipped/docked vessel that may have been damaged in slip. There was visible rub marks on the auxiliary engine of the docked vessel. 
  
  AMBULANCE/TRANSPORT 
  Ambulance unit arrived at 1733 hours and took over patient care. Park Staffer and I assisted in wheeling the gurney to the ambulance once VICTIM was strapped on and secure. VICTIM was in the ambulance at 1740 hours. The ambulance transported VICTIM to Logan Regional Hospital for further care a short time later, once additional crew members arrived. 
  
  VESSEL ASSIST 
  I asked USCG Vessel to assist with towing VESSEL #1 to the boat ramp where other party members would load it on the trailer. USCG Vessel and it's crew were still in the marina and agreed to assist. They had VESSEL #1 in tow at 1806 hours. 
  
  
  On 9/7/2014, I was asked to identify the owner of VESSEL #1 for the report including some required personally identifying information. The owner of VESSEL #1 was not on scene when the incident occurred. I was able to locate only a name and address of the owner per the vessel registration paperwork. In order to further identify the owner I was required to do a name search in state driver license files. No phone number was included in the file so I was unable to confirm I had found the owner of VESSEL #1. With the presumption this was the owner of VESSEL #1, this individual's personal information was included in the report on 9/8/2014.