Suppose that a witness testifies before a grand jury. Suppose, then, that the grand jury questions other witnesses whose testimony casts doubt on the first witness's testimony, and then summons the first witness again.

The witness invokes her Fifth Amendment privilege against self-incrimination. The special prosecutor assisting the grand jury wants the witness's testimony, but is not willing to give the witness immunity.

Two questions:

First, what is the effect if the judge orders the witness to answer the grand jury's questions?

Second, if, under compulsion (immunity or the threat of being jailed for contempt), the witness gives testimony that is materially different from her initial testimony, can her second round of testimony be used against her in a prosecution for perjury?

(I answered these questions here and here, but in light of current events in the 185th Grand Jury I'll bring them together here and simplify.)

Effect of Compulsion

The Fifth Amendment says that no person "shall be compelled in any criminal case to be a witness against himself." If a judge orders the witness to testify and she gives self-incriminatory answers, she has been compelled to be a witness against herself; her compelled testimony can't be used against her, either directly or indirectly.

If, on the other hand, the special prosecutor gives the witness immunity and she gives self-incriminatory answers, she had been compelled to be a witness against herself; her compelled testimony can't be used against her, either directly or indirectly.

(If, on the third hand, the special prosecutor skips the judicial process and instead waterboards the witness and she gives self-incriminatory answers, she has been compelled to be a witness against herself; her compelled testimony can't be used against her, either directly or indirectly.)

From the point of view of the witness who is happy to testify with immunity—who is trying to protect only herself and not someone else (for example, her boss)—the effect of formal immunity and the effect of compulsion are identical. She can accept immunity, or she can be ordered (over her objection) to answer the questions, and she's in good shape.

From the point of view of the witness who is determined to protect her boss, though, it's better to be ordered to answer the grand jury's questions than to get use immunity. Either way, she can be held in contempt and jailed for failing to answer the questions. If she wants to fight on, she has to file a petition for writ of habeas corpus and take it up on appeal.

If she's jailed for contempt after explicitly being given immunity, she doesn't have as good an argument on habeas, she's less likely to make bail pending the appeal, her lawyers won't be able to keep the appeal alive as long, and she won't ultimately prevail.

If she's jailed for contempt after being ordered to testify, she may prevail on habeas, in which case the special prosecutor can turn around and give her use immunity. Time will have passed, though—maybe enough time to get her boss through the Republican primary.

With regard to the 185th Grand Jury and Rachel Palmer, Newman writes:

Recent legislation has indicated that the power of all existing Grand Juries across the State will cease at the end of the year and all new ones must be empaneled at the beginning of the New Year.  Word on the street is that Lykos and Crew are eagerly anticipating all this Grand Jury work to be for nothing, but there is disagreement amongst the legal scholars over whether or not a previously authorized hold-over Grand Jury can continue.

Here's the mentioned legislation—Texas HB79.

Newman also writes:

The basis for which St. Martin and Mount are asking the Court to compel Rachel to testify is that their questions are not incriminating.  The questions are sealed and nobody but the parties know what they are at the moment.  Under the Special Prosecutors' position, there is no need for immunity to be offered if the questions wouldn't require anything for there to be immunity from.  At some point during the hearing, Judge Brown made mention of the possibility of Immunity being offered to Rachel, and both Mount and St. Martin were seen shaking their heads in unison.

If St. Martin believes that the questions the grand jury has do not implicate the right against self-incrimination, he should be perfectly happy to give Palmer use immunity—especially if the grand jury might be disbanded at the end of the year (doubtful). He could have given her immunity and gotten her before the grand jury last week, and she either would have answered the grand jury's questions or would be languishing in the Harris County Jail by now.

In fact, while it's all the same to the witness, it's not all the same to the judge, and the battle to get Palmer to testify without giving use immunity is one that St. Martin may well lose:

A trial court “cannot compel a witness to answer unless it is perfectly clear, from a careful consideration of all the circumstances in the case, that the witness is mistaken in asserting the privilege, and that the answer cannot possibly tend to incriminate the witness.”

. . . . .

When a witness invokes his Fifth Amendment right against self-incrimination on the advice of the witness's counsel, the trial court is not obligated to make any further determination.

Boler v. State, 177 S.W.3d 366, 371 (Tex. App.—Houston [1st Dist.] 2005, pet. ref'd).

Judge Brown doesn't even have to look into the basis for the invocation of the Fifth [update: yes she does, according to Walters v. State, which the CCA just handed down]; if she does, she can't compel responses unless it is "perfectly clear" that the answers won't be incriminating, and she can't ask Palmer (because of the Fifth Amendment) or her lawyers (because of lawyer-client privilege) questions to make that determination. If Judge Brown declines to order Palmer to answer the grand jury's questions, St. Martin will have to give Palmer immunity to get her testimony; if Judge Brown orders Palmer to answer the grand jury's questions, Palmer may take the issue up to the court of appeals.

Sometimes lawyers' egos get in the way. Maybe someone else can suggest to me another reason that St. Martin wouldn't immunize Palmer and send her on her way.

At any rate, I hope we all can agree that the effect of Judge Brown's order compelling Palmer to answer the grand jury's questions would be to make the answers to those questions—and any evidence obtained based on those answers—unavailable as evidence against Palmer in the event that she were accused of some crime.

On to the second question:

Immunity and Perjury

This point seems such a fundamental part of the Fifth Amendment that it shouldn't require discussion: if, under use immunity, a witness admits committing a crime in the past, that testimony cannot be used against her in a prosecution for that crime. The rule is the same regardless of what the past crime was—even if it was perjury.

Yet some lawyers seem to think that a person might be prosecuted for an earlier statement that a witness, while under use immunity, admits was perjurious.

An immunized witness can't lie to the grand jury and then claim that use immunity was immunity from prosecution for perjury. Immunity is not a license to lie. This is probably the origin of the theory that immunized testimony might be used against a witness in a prosecution for earlier perjury (but not murder, or robbery, or rape).

The Department of Justice, though, gets it right:

A grant of immunity does not protect a person from a perjury charge if he or she testifies falsely. The immunity grant means that immunized testimony cannot be used to prove that a previous sworn statement was false. Thus, if two sworn statements are irreconcilable and one was made after an immunity grant, the government must prove that the one given under the immunity grant was the false one. The government may prove immunized testimony is false by using other immunized testimony from the same grant of immunity "so long as that testimony conforms to otherwise applicable rules of evidence."

(U.S. Attorneys Manual, Criminal Resource Manual 1758 (citations omitted).) This is Fifth-Amendment law, and the rule is no different in state court than in federal court.

That immunized testimony can't be used to prove prior perjury is such an obvious rule that there don't seem to be any Texas cases on point. The Texas Court of Criminal Appeals states the balance of the rule correctly:

The one nearly universal exception to the scope of the immunity granted is that a witness who perjures himself while testifying under compulsion is not immune from a prosecution for perjury. That the Fifth Amendment provides no protection for the commission of perjury “has frequently been cited without any elaboration as to its underlying rationale.” Requiring the testimony to be truthful does not in any way render the grant of immunity conditional, because the “law requires the answers of the witness under oath to be truthful.” Perjured testimony is an obvious and flagrant affront to the basic concepts of judicial proceedings. Neither the text nor the spirit of the Fifth Amendment confers a privilege to lie.

(Butterfield v. State, 992 S.W.2d 448, 450 (Tex. Crim. App. 1999) (emphasis added).) Unlike the actual rule, a rule allowing the use of immunized testimony to prove prior perjury would be conditional, and would not satisfy the FIfth Amendment.

If Palmer lied under oath when she first testified before the grand jury, and if she testifies again under compulsion—whether an explicit grant of immunity or a court order—whatever she says there can't be used to prove that she lied the first time. Unless she's trying to protect someone else, she should be okay testifying truthfully now, whether her use immunity is explicit or de facto.