RedactedNarrative: On 08/11/2021, I, Conservation Police Officer, became aware of a boat accident via voicemail. I contacted the boat owner who informed me his sailboat was involved in an accident with another sailboat during a regatta on Lake Michigan. I requested information from owner and advised him to email me.
  
  On 08/18/2021, he emailed me the information I requested. He stated the following occurred:
  
  On Wednesday, 08/04/2021, Yacht Club was hosting a regatta (Chicago Beer Can Series) on Lake Michigan. The regatta was approximately 2 miles southeast of Navy Pier. The sailboat owner, was on board while his brother,  Operator 2, was operating the sailboat called (Vessel 2). Operator 2 was on a starboard-tack while the other sailboat,  (Vessel 1) - operated by Operator 1, was on a port-tack perpendicular to each other. O2 was on the starboard side of vessel as O1 approached at approximately 3.5 knots. O1 called out "Starboard" several times to vessel to give them ample time to manuveur and avoid a collision. O2 realised vessel was not turning so they turned to their starboard side, as that occurred vessel turned to their starboard side as well. O2 slowed to 1.8 knots at the time of the collison with vessel. No injuries were reported; damage reported: to fiberglass hull side and top, and the teak toe rail was shattered. After the collision both sailboats continued with the race. Estimated damage to O2 was $3,000.
  
  Owner was unable to provide me with boat information other than the name  but knew the operator was O1 and owner. 
  
  08/25/2021, I contacted O1, he seemed hesitant to provide information regarding the accident and advised he was busy with work at the moment, but was available tomorrow (08/26/2021) at 3 pm to discuss the event.  
  
  I contacted the boat owner of V1, who was not on the boat at the time but told me the following occurred: V1 was on a port-tack, and stacked up by 3 other sailboats and their manuverbility was limited. He stated V1 was the giveway vessel but O2 should have turned away much sooner because they to have a responsibiltiy to avoid a collision (Mentioned Rule 10). When O2 did turn they should not have turned as sharply as they did it caused the back end to swing in front of V1. There is a "protest" being held at Columbia Yacht Club regarding the accident next week. There was a minor dent on Free Radical but no injuries reported on his boat.  
  
  I requested owner to email his information and a written statement as to what we discussed over the phone. Subject will send me the protest paperwork as well.
  
  O2 was not registered at the time of the accident; registration was submitted on 08/11/2021 after I contacted owner regarding the accident. 
  
  I contacted US Coast Guard and IDNR administration to determine if the regatta was a permitted event, no permits were located regarding the event that occurred on 08/04/2021. Investigation pending