PETTY CHARGE FOR THEFT. THE FIRST REACTION, WHY NOT GET YOUR BADGE. A PARKING LOT CONFRONTATION ESCALATES. ALL OF IT CAUGHT ON CAMERA. JUST FORCE ALAN? OR EXCESSIVE FORCE? YOU WANT TO SEE MY GUN? NO GUN WENT OFF BUT PLENTY OF VERBAL SHOTS WERE FIRED. THIS WAS CAUGHT ON TAPE. SOMETHING YOU'LL HEAR ON LOCAL 10. WE HAVE IT ALL, LIFE. Reporter: POLICE HERE TONIGHT ARE IN THE HIT OF A FULL-BLOWN INTERNAL AFFAIRS INVESTIGATION, ALL THIS PROMPTED NOT ONLY BY THIS BIZARRE CONFRONTATION BUT BY AN AUDIOTAPE, SOMETHING YOU'LL HEAR ONLY ON LOCAL 10. (SIRENS). IT IS A STUNNING SOUNDTRACK. SURPRISING STATEMENTS. STARTLING FLAT-DOWNS. YOU WANT TO SEE MY GUN? Reporter: A SHOCKING SHOW OF FORCE. HE WOULD HAVE STOPPED ME OVER OTHER PARKING SPACE. Reporter: ALL AT THE HANDS OF A NORTH MIAMI OFFICER THAT THEY SAW ILLEGALLY PULL INTO IS A PARKING SPACE. IT'S CRAZY. Reporter: THE CRAZY BEGAN LAST MONTH. I CAME HOME, CAME TO THE LOT. Reporter: SHE CAME IN THE WRONG WAY THROUGH A ONE-WAY STREET AND AS SOON AS HE GOT OUT, HE HEARD SCREAMS. HE SAW SOMEONE RUNNING TOWARDS HIM. I DON'T KNOW IF I'M BEING ABLE TACKED OR IF THERE'S A COMMOTION. I WENT HERE TO GET A CAMERA AND HID THE VIDEO. ARE YOU SPECIAL? Reporter: ONLY THE AUDIO WAS CAPTURED. GET YOUR HANDS OFF. MY LAST TIME. HERE IS THE POLICE I.D. THAT'S MY COP CAR THAT'S PARKED THERE. I AM ON DUTY 24/7 BECAUSE WE'RE IN MY CITY. ARE YOU ON DUTY? NO. REGULATION YOUR BADGE? IN MY HOUSE. YOU WANT TO SEE MY GUN? DID YOU TAKE THAT AS A THREAT? IMMEDIATELY. I KNEW THAT FIREARM WAS THERE HE MIGHT HAVE SHOT ME. Reporter: WE FRONTED OFFICER STEVE UMMUST WHILE HE WAS ON LIGHT DUTY AT THE NORTH MIAMI POLICE DEPARTMENT. AND IT DIDN'T TAKE LONG TO JOG HIS MEMORY. HE QUICKLY EQUIPMENTED IT WAS HE SAID YOU WANT TO SEE MY IFING GUN IS THAT PROPER PROCEDURE? NO. Reporter: THE OFFICER HELD A DIFFERENT STORY, SAYING I BEGAN WITH THE SPEEDING INTO THE LOT, ALMOST RUNNING DOWN THE OFFICER'S 13-YEAR-OLD SON. IN THE RECORDING YOU DON'T SAY ANYTHING ABOUT THE CHILD P. AND HE SAYS HE WAS THREATENING AND CAME TOO CLOSE, LIKE THIS. CAME RIGHT UP TO YOU AND YOU PUSHED HIM JUST LIKE THAT. HE WAS THREATENING ME BY MAKING CONTACT WITH ME. Reporter: HE FELT SO THREATENED HE SAYS HE CALLED POLICE FOR BACKUP WITH A SPECIAL DIRECT FULL. WHY DIDN'T YOU JUST DIAL 911? BECAUSE IT'S MUST FASTER TO DIAL HERE. Reporter: WE'VE LEARNED, THOUGH, THERE IS NO RECORDING OF THAT CALL, ACCORDING TO POLICE. THEIR PERSONNEL FILES SHOWS HE HAD BEEN AN OFFICER FOR MORE THAN 15 YEARS, RATED ABOVE SATISFACTORY AND HAS COMMENDATION AFTER COMMENDATION, CERTAINLY NOTHING LIKE THIS. DON'T YOU THINK YOU SHOULD BE DISCIPLINED FOR SOMETHING LIKE THAT? NO. Reporter: HE NEVER WENT TO POLICE AND NOW FEELS HE NEVER CAN. I'M AFRAID. Reporter: THE ONLY PROTECTION HE BELIEVES IN IS TATTOOED UP AND DOWN HIS ARM. THE VERY ARM THIS FORMER FOOTBALL PLAYER SAYS DIDN'T PROVOKE, DIDN'T PUSH BACK, DIDN'T PROVIDE ANY EXCUSE FOR THE OFFICER OR MENTIONED A PISTOL. I DON'T THINK ANY AUTHORITY SHOULD ACT THAT WAY. TONIGHT BOTH MEN DISAGREE WITH EACH OTHER'S OTHER'S VERSION. THE CITY MANAGER WOULD ONLY SAY HE DOES EXPECT ALL OFFICERS TO BEHAVE THE SAME OFF DUTY AS THEY DO WHEN THEY ARE ON. THERE IS A FULL-BLOWN INTERNAL AFFAIRS INVESTIGATION UNDERWAY AND AS SOON AS WE GET RESULTS