DeFede

MIAMI (CBS4 I-TEAM) ― Last month's shooting on the MacArthur Causeway – in which an alleged carjacker was shot to death – involved more than just a pair of on-duty Miami Beach police officers; it also included a retired cop and a civilian employee of the Miami Beach Police Department.

The June 18 causeway shooting, which left 29-year-old Lawrence McCoy dead, was a chaotic Wild West-like scene. Between 20 and 40 shots were fired, according to sources familiar with the investigation.

Police claimed McCoy attempted to rob a cab driver on South Beach around 11 p.m., pistol whipping the cabbie and taking his car. The police then said McCoy fled in the cab driving west in the east bound lanes of the Macarthur Causeway, crashing head on with another car.

McCoy, according to police, came out of the cab with a gun and began firing at police officers who returned fire. Police say the gun battle continued as McCoy ran down the causeway before finally being killed at the base of the bridge leading to Miami Beach near the Coast Guard station.

In its initial reports to the press, the police never mentioned that a retired officer, Steve Stuart, or a civilian Miami Beach police employee, Gisela Tacoa, was involved in the shooting.

On June 22, the Miami Beach Police Department did put out a press release identifying Stuart and Tacoa as being involved in the shooting.

CBS4 News erroneously reported in an earlier version of this story on its website that police had not released the names.

Sources tell the I-Team that Stuart and Tacoa just happened to be present on the causeway – and armed – when they saw the on-duty Miami Beach police officers chasing McCoy.

Tacoa, 35, a police public service aide, has been placed on administrative leave.

"A serious crime was being committed and she wanted to help," said Richard McKinnon, president of union Local 3178 of the Communications Workers of America, which represents Tacoa. "They are doing an investigation and she is suspended without pay until that investigation is complete."

Although police said McCoy had fired at the officers, the I-Team has learned that police did not find a gun on McCoy after the shooting. In fact, a search of the causeway that night and the next day turned up no weapon. It wasn't until June 20 or later that police say they found a gun in the water under the bridge where McCoy was shot.

One reason police believe the gun they found was the same gun used by McCoy is the fact that it did not show signs of being in the water for very long. It is unclear if there is additional evidence linking McCoy to the gun they found days later in the water.

Miami Beach Police Chief Carlos Noriega has scheduled a press conference for Thursday at 2 p.m. to answer questions about the causeway shooting as well as a June 15 shooting in which an unarmed man was shot to death outside a club on South Beach.

The earlier shooting of 29-year-old tourist Husien Shehada has touched off protests on Miami Beach. Media attention recently has focused on Officer Adam Tavss, who was involved in both the Shehada shooting and the McCoy shooting.

But news that a police service aide was in the middle of the causeway shootout, coupled with the fact it took several days for police to find the suspect's gun in that case, may open a new line of questions.

For instance, why didn't police send divers into the water to find McCoy's gun on June 19? Why did they wait? And what proof can they provide that the gun they recovered from the water was actually McCoy's?

(© MMIX, CBS Broadcasting Inc. All Rights Reserved.)

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