The blanket pardon is only for past acts.

That's correct. The injecting COVID into the prisoners thing obviously would have taken place during the years the pardon covered.

His legal argument here is that Sen. Paul is only doing this in order to induce Fauci to make new public statements before Congress that will be prosecuted for political reasons, regardless of whether they are true or not. Therefore (goes the argument) Fauci can reasonably take the Fifth Amendment so that his statements won't be used against him in a future prosecution.

Brown v. Walker of 1896 is the case that covers pardons and witness testimony. The Supremes found that the pardon is absolute and that a witness can't be chased after further. They wrote, citing an earlier case

The power thus conferred is unlimited, with the exception stated. It extends to every offense known to the law, and may be exercised at any time after its commission, either before legal proceedings are taken or during their pendency, or after conviction and judgment. This power of the President is not subject to legislative control. Congress can neither limit the effect of his pardon nor exclude from its exercise any class of offenders. The benign prerogative of mercy reposed in him cannot be affected by any legislative restrictions.

Paul can fume all he likes, but he can't prosecute Fauci for perjury for something he said 4 years ago. He also can't prosecute him if he claims Fauci's perjuring himself *today* because pardons cover activities (and Fauci would be answering about those things he was pardoned for).

What he CAN be prosecuted for is Contempt of Congress, and I imagine Paul's staff is drawing up the paperwork for that.

Brown v. Walker is also used to establish that witnesses with pardons are compellable, within limits. I guess this is one of the foundational cases for rules around witness testimony:


Stringent as the general rule is, however, certain classes of cases have always been treated as not falling within the reason of the rule, and therefore constituting apparent exceptions. When examined, these cases will all be found to be based upon the idea that, if the testimony sought cannot possibly be used as a basis for, or in aid of, a criminal prosecution against the witness, the rule ceases to apply, its object being to protect the witness himself and no one else, much less that it shall be made use of as a pretext for securing immunity to others.

1. Thus, if the witness himself elects to waive his privilege, as he may doubtless do, since the privilege is for his protection, and not for that of other parties, and discloses his criminal connections, he is not permitted to stop, but must go on and make a full disclosure.

(It seems this is the principle where once you start answering questions, you can't stop)

2. For the same reason, if a prosecution for a crime concerning which the witness is interrogated is barred by the statute of limitations, he is compellable to answer.

3. If the answer of the witness may have a tendency to disgrace him or bring him into disrepute, and the proposed evidence be material to the issue on trial, the great weight of authority is that he may be compelled to answer, although, if the answer can have no effect upon the case except so far as to impair the credibility of the witness, he may fall back upon his privilege....But, even in the latter case, if the answer of the witness will not directly show his infamy, but only tend to disgrace him, he is bound to answer.

4. It is almost a necessary corollary of the above propositions that, if the witness has already received a pardon, he cannot longer set up his privilege, since he stands, with respect to such offense, as if it had never been committed.

On that last point the court cited that "if the fact of the witness being in danger be once made to appear, great latitude should be allowed to him in judging for himself of the effect of any particular question."...which is very likely what Fauci's lawyers are relying on.