Can a prosecutor use coercive and threatening language to compel a witness to testify at trial?

The record indicates the language used by the prosecutor here was not only threatening and coercive but, "effectively drove [the] witness off the stand." (Webb v. Texas, supra, 409 U.S. 95, 98, 93 S.Ct. 351, 353, 34 L.Ed.2d 330.) Because the witness thereafter refused to testify, the threat created an implied admission of guilt of perjury whether or not it was an actual admission, thus further damaging appellant's interests in receiving a fair trial by the court.