RedactedNarrative: V2 WAS TROLLING IN LAKE ST. CLAIR WHILE V1 WAS MOTORING ENROUT TO HARSEN'S ISLAND.  V1'S WINDSHIELD WAS FOGGED AND NOT PAYING ATTENTION TO SURROUNDINGS. 
  
  V2 WAS IMMEDIATELY OFF THE BOW OF V1.  V1 COLLIDED HEAD ON WITH V2 AND PROCEDED TO DRIVE OVER THE TOP V2.  V2 OPERATOR ENTERED THE WATER DUE TO COLLISION. V2 OPERATOR WAS ABLE TO GET ONBOARD V2.  V1 TOWED V2 TO BOAT RAMP.  NO INJURIES REPORTED.  V1 AND V2 BOTH HAD PFDS. V1 USED PFD, BUT NOT KNOW IF WORN BEFORE ACCIDENT.  ALCOHOL WAS NOT A FACTOR.