Revealing mistake: In the beginning of the scene right before Street and Hondo are in the car talking about where they used to serve the camera shot from outside shows the car driving along the road and also a man with a blue cap and backpack looking into the camera, then quickly turning his head away. (00:25:10)
Revealing mistake: When the team is chasing Gamble (and company) from the police truck (that they freed Montel from), through the subway, and then through the sewer, Sanchez's watch changes from the left hand to the right hand and back again. (01:22:50 - 01:25:15)
Revealing mistake: As Street climbs into the back of the subway, Hondo has the light on his gun focused on into the subway car. But as he lowers his gun to climb in himself, an external light source is switched on to make it look like a flash is on him. (01:26:25)
Revealing mistake: When we see the close up of the jet after having landed on the bridge, look closely at the right main landing gear. There is a rope or a chain that slows down and stops, seems to be a device to move the aircraft without having the engines run. (01:34:50)
Revealing mistake: In the playing card target shooting sequence, Colin Farrell shoots an ace from the front but the card explodes from the rear. A squib was used to make the hole in the card, blowing the pieces outward instead of inward.
Revealing mistake: When the S.W.A.T. Team is going after TJ and the ex SWAT member in the subway station, they say they are at the 7th/Metro Station. If you look on the wall after the subway moves, the signage says Wilshire/Normandie.
Revealing mistake: During the shoot-out between Hondo and TJ near the beginning, the two of them are running towards their targets and the view is from TJ's right side. As TJ is closing on his target, his pistol jams with the slide locked back, yet he acts like he is shooting normally. The sound of gunfire is added.
Answer: The SWAT Captain originally kicked Street and Gamble off the team and out of the SWAT Division completely for disobeying orders resulting in a hostage being shot. The SWAT Lieutenant convinced the Captain to keep the two officers in the division on a probationary basis to work back towards getting back on the team. Gamble was insulted by the probationary assignment and later resigned. The Captain offered Street the chance for immediate reinstatement to the team if he placed all blame on Gamble. When Street chose the probationary assignment over blaming Gamble or resigning alongside Gamble, everyone assumed Street cut some type of deal to remain in the SWAT Division without knowing the whole story.