Libby should never have had to testify. He was called in on a subpoena on a phony, non-existent crime. How about we charge you with wearing blue shoes and bring you into the grand jury. During the prosecutor's questions, you say you only wear red shoes. They find out that you once wore blue shoes, and indict you for perjury. Who cares if what you misspoke about didn't pertain to an actual crime?
It's like evidence obtained by a violation of the law, which is subject to the exclusionary rule.
exactly my pt. well said. this whole thing is a bunch of barbara streisand.