Visible crew/equipment: When Juror 8 is approaching Juror 4 following the revelation of the witness across the street's eyesight being put under question, as the camera moves in, its shadow is seen moving across the back of Juror 3. (01:28:55)
Deliberate mistake: When Henry Fonda decides to recreate the old witness' ability to get to the door in 15 seconds, he asks another juror to time his walk. The scene never cuts away, but the juror who times it says it took 41 seconds when in reality it takes exactly 31 seconds, you can time it.
Visible crew/equipment: In the scene where Henry Fonda is recreating the testimony of the old man getting out of bed & walking down a hall, you can clearly see a shadow of the camera on the floor.
Factual error: When the jury first enters the deliberation room, there's a newspaper on the table that at least two of the jurors look through. Jurors are not allowed newspapers during deliberations.
Continuity mistake: Early in the film, Henry Fonda and another juror are in the men's room. When the other juror exits, the door is a swinging door. From the jury room the door is a regular door with a door knob. You can hear the door close when Henry Fonda exits and closes the door.
Answer: If you're referring to the jurors, no. We see the entirety of their deliberations. If you're referring to the prosecution or defense, that is unknown. Given, however, that none of the jurors brought up the question, it's likely there was at least a check of his clothes to verify he had a hole in his pocket.
Given how easy it would be to simply tear a hole as an excuse, even if it was there, it wouldn't be much in the way of corroboration.
LorgSkyegon