The reality is that it doesn't.
It happens on TV.
It happens in the movies and it's very dramatic when it happens in the movies.
Remember the movie “A Few Good Men” with Tom Cruise and Jack Nicholson? Remember the pivotal courtroom scene where Tom Cruise is cross examining Jack Nicholson about the fact that he cannot handle the truth? Remember how Jack Nicholson breaks down and blurts out that he clearly did something wrong but it was for the benefit of his unit and country?
You remember the movie “The Verdict?” with Paul Newman as a down and out drunk lawyer who is trying a medical malpractice case in Boston? The key dramatic scene is once again in the courtroom when he is cross examining a medical witness.
These dramatic movies clearly make it seem as if witnesses break down on cross examination all the time. The reality is just the opposite.
Lawyers who aspire to become trial attorneys will often have visions in their mind about how to conduct a great cross examination that gets the adverse witness to admit everything they're trying to prove. Once again, this is fantasy and not reality.
When an attorney screams and yells during cross-examination, the jury will take pity on the witness, no matter what he's accused of. Many times the jury does not understand why there's so much hostility by the attorney when questioning a hostile witness.
A lawyer who gets up to cross-examine a witness has an agenda to fulfill. Either he's going to show that the witness is not credible, and has inconsistencies in his testimony or he's going to use that witness to bolster the testimony of his own witnesses.
There are some attorneys who prefer to use kindness as a method to obtain information from the witness as opposed to being a pitbull animal.
While it certainly can happen the witness will break down and reveal things they otherwise would not have said, that is a rare exception in civil cases involving medical malpractice lawsuits, accident lawsuits and wrongful death lawsuits here in New York.
Lawyers and litigants can fantasize as much as they want about what might happen during cross examination. The reality is that an attorney must be fully prepared and have a clear goal of what he wants to accomplish during cross examination of a key witness. If the questioning happens to lead to total breakdown, that's fine. However, that is rarely the goal of an experienced trial attorney.