It is an obligation of an advocate, in cross-examination, to convey to the witness the evidence the advocate intends to adduce to rebut the evidence of the witness. This is called “putting” the case to the witness. The witness will have the presumed opportunity to comment on the “case” of the advocate’s witnesses.
The potential penalty for failure by the advocate to do this is a prohibition by the court on the advocate adducing evidence contradictory of the witness’ evidence. In fact, the advocate will, in such circumstances, concede the failure and ask for leave to, belatedly, “put” the case to the witness or witnesses. This may not be convenient (it usually is not) and may be impossible. It will certainly cost money. The cost will be met by the advocate’s client. The court ensures this by permitting the witness to return, conditional on the advocate consenting to an order against his/her client on the costs.
There are often matters on which the advocate has no evidence to present in rebuttal. That does not preclude the advocate from seeking to challenge the witness on the point or points. However, the advocate is not permitted to leave the witness under the mistaken impression that the challenge is the “putting” of the advocate’s case. To avoid this, the advocate “suggests” to the witness that “…………….”. This formulation is a signal to the witness that the advocate is asking the witness to agree or disagree with the advocate and that the advocate is not going to call rebuttal evidence.