Another thing I want to point out that I haven’t seen mentioned. When there’s an objection that’s been sustained, something that always happens but you don’t see in the courtroom dramas is that the lawyer who objected will then immediately ask that the part objected to be stricken from the record.
The reason for this being that whole jurors could remember some things, and might take notes on general things, they will fall back on and use the court record while deliberating to actually remember the specific questions and answers given. So if there was something asked or said which had a sustained objection, it won’t be there when they do that.
Now as others have also said, depending on the gravity of the objection, as the saying goes, “you can’t unring a bell” and the judge may be forced to take other actions beyond instructing the jury to disregard those comments.
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