Legal practitioners easily forget how arcane it is to do what they do. When the time comes they recognise one thing; giving evidence is intimidating.
It is intimidating even if the advocate asking them questions is inept and persists in making mistakes of various kinds (it happens).
Those mistakes may arise out of ignorance of the law of evidence and/or the necessary procedures to conform to that law.
Normally, the evidence for the Plaintiff is presented to the court first. The reason for this is that the burden of proof lies on the Plaintiff; he/she it is who is making allegations about the Defendant. The case is about those allegations, nothing else; (except where there is a counterclaim).
When all the evidence (from witnesses or otherwise) of the Plaintiff has been presented to the court, the Defendant will call his/her witnesses to rebut that evidence of the Plaintiff. That is, this will happen assuming the Plaintiff has made out a prima facie case. A prima facie case is one which, in the absence of rebuttal evidence from the Defendant, will entitle the Plaintiff to a verdict.
When a party calls a witness to give evidence, the advocate for that party is not permitted to “lead” the witness. That means that the questions put to the witness should not suggest the answer. Such questions are called “leading questions”. As a rough (but mistaken) rule of thumb, if the answer to the question is “yes” or “no”, the question is a leading question.
In practice, some leading questions are permitted. They are very useful to introduce non-controversial facts about the witness, for instance.
The examination of a witness by the advocate calling that witness is called “examination in chief”. It is more difficult to do this than it is to “cross-examine”. What the advocate must avoid doing, is to give the evidence himself/herself. A leading question has this effect; it suggests to the witness the evidence he/she should give.
Consequently, some witnesses struggle to answer questions in examination in chief, because they are surprised by the circumspect character of the questions. They come to life during the “cross-examination”.
“Cross-examination” is the process whereby the advocate for a party asks questions of the witness called by the other party. That advocate is not restrained in the form of the questions asked; leading questions are permitted. (Cross-examination is not bullying; bullying is not permitted).
To say that an advocate may ask leading questions is not to suggest that that, or any advocate, is completely free in the questions asked. Only relevant evidence is admissible in a trial; irrelevant evidence is inadmissible, therefore questions about irrelevancies are not permitted.
It is the job of the opposing advocate to ask the judge to disallow such questions. (Unless it is thought better to leave the opponent to drown in those irrelevancies).
Furthermore, it is the job of the Defendant’s advocate to, in due course, in cross-examination, give the Plaintiff’s witnesses an opportunity to comment on the case which the Defendant’s witness or witnesses will say in relation to the matters testified to by the Plaintiff’s witnesses. (The penalty for the Defendant if this does not happen can be severe).
When cross examination is finished the advocate who called the witness has a chance to ask further questions of the witness, but only to address new matters arising from cross-examination and requiring clarification.
The trial will proceed in this fashion with each witness being called and asked questions, first in examination in chief, then in cross-examination and then, maybe, in re-examination. Then the next witness is called.
The reason why cross-examination is so prominent in the mind of a witness is that the major purpose of those questions is to undermine the evidence given by the witness. This is not to say that that process will be successful; often it is not. In fact, cross-examination may “free” the witness to address the evidence again and deliver it more cogently and persuasively than first time around.