RedactedNarrative: V1 backed out of the boat slip with stern facing into the canal.  V1 turned to its starboard side to face towards the exit of the marina. V1 still had a dock line attached to its starboard side. As V1 pulled further away from the dock, the line tightened. This caused V1 to make a sharp turn into V2, parked in the next slip to the East. V1 pulled forward and the dock line loosened. As V1 continued to pull forward the dock line tightened again. This caused V1 to collide with V3, parked in the next slip the the West.