After being pardoned, can one be forced to testify in civil and criminal cases?

Question

After being pardoned, can one be forced to testify in civil and criminal cases with no protection against self-incrimination?

My example is how Trump has pardoned former Arizona sheriff Joe Arpaio; does Arpaio's protection against self-incrimination disappear if he accepts the pardon for his conviction of a federal crime?

Can Arpaio be compelled to testify in cases brought against him, such as federal and state cases that concern his past actions as sheriff?

I.e., such as civil or criminal cases concerning Arpaio's department's past treatment of prisoners, instances of racial profiling and immigration-related cases?

Can Arpaio be compelled to testify against co-defendants in the same case(s) he was being prosecuted for that were nullified by the pardon?

Is there a difference between between civil and criminal cases as to what he can be compelled to do? And a difference between state and federal cases?

Can Arpaio decline the pardon in order to protect himself from being forced to testify?

And, can Trump preemptively pardon Arpaio, as the pardon states for any other offenses... that might arise, or be charged, in connection...?

Answer 1

This analysis by UCLA law professor Eugene Volokh concludes that the answer is yes.

A person may refuse to testify, even when subpoenaed, on the grounds that the testimony may expose him to criminal liability. But if the prospect of criminal liability disappears — whether because he has been granted adequate immunity by prosecutors, or because he has accepted a presidential pardon — then the privilege against self-incrimination also disappears.

Of course, Arpaio could still claim (plausibly, in my opinion) that his testimony would incriminate him as to other crimes with which he has not been charged / convicted / pardoned. (Unless the pardon was so broad as to cover all related federal crimes of which he might have been guilty; I cannot find the exact text of the pardon.) He could also claim that his testimony would incriminate him as to crimes under state law; the President cannot pardon those.