A day later, that terrible call is even more embarrassing to baseball. First there was the arrogant umpire press conference, where of course they claimed they didn't do anything wrong. It was interesting, that the homeplate umpire during the press conference never said he was positive that the ball was not caught.
You would think an umpire would only rule it a dropped ball if he was positive the ball was actually dropped. From what I've seen, here's my guess of the thoughts of the umpires during the infamous play.
Homeplate umpire: "Strike three! Time for my between innings Whiskey shot! Wait, why's that guy running? Maybe the catcher dropped it? I guess that might have happened, I'll give it to him. He would never try to deceive me."
The other umpires when Mike Scioscia appealed to them after a long argument: "No way in hell I'm overturning that call! We don't get paid overtime if this thing goes into extra innings. Besides, we're in Chicago; they had a riot over disco once -- I'm not taking any chances. Now where did I leave my crack pipe?"