Bill Barr has sounded the death knell on Trump's wild claims

The fact that the announcement comes from Barr makes it hit particularly hard for Trump. Over his nearly two years in office, Barr has repeatedly distorted the truth to benefit Trump, and he has used the Justice Department to intervene selectively in politically-charged cases to the benefit of Trump’s political allies.
Barr even took pains to amplify Trump’s pre-election claims of potentially massive voter fraud. In a June 2020 interview with NPR, Barr opined (without evidence) that mail-in ballots present “so many occasions for fraud there that cannot be policed. I think it would be very bad.” And in Congressional testimony just weeks later in July 2020, Barr tried and failed again to conjure the demon of massive fraud in mail-in ballots.
Yet part of the beauty of the Justice Department is that ultimately, it follows facts, not wild conspiracy theories. And even though Barr changed the rules and instructed prosecutors specifically to investigate potential instances of voter fraud (and potentially announce those findings publicly) immediately after the election, they apparently found nothing of note.
Trump’s increasingly desperate legal team, headed by Rudy Giuliani, immediately disputed Barr’s conclusion: “with all due respect to the Attorney General, there hasn’t been any semblance” of an investigation.
Trump's election challenges put lawyers' credibility on the line
Let’s break that down. In one corner, we have Giuliani and the rest of Trump’s legal team, who have continually had their cases thrown out of court for complete lack of evidence. “Charges require specific allegations and then proof. We have neither here,” wrote a Trump-appointed federal judge last week in a stinging rebuke to the campaign’s efforts to undo Pennsylvania’s vote count certification. In the other corner, we have Barr and the entire Justice Department looking for fraud and finding nothing. Take your pick.

Throughout his tenure, Barr can, and has, bent the truth and diminished the Justice Department by using it for transparently political purposes. But facts are facts. It’s one thing to twist them; it’s another thing altogether to fabricate them where they simply don’t exist. If Barr and the Justice Department couldn’t provide support for Trump’s conspiracy theory, then nobody can.

Now, your questions:

Bonnie (Connecticut): I thought the Constitution states a president has pardon power except in cases of impeachment. Shouldn’t President Trump therefore lose the power to pardon?

No, but the confusion here is understandable. Article II of the Constitution provides that the President “shall have power to grant reprieves and pardons for offenses against the United States, except in cases of impeachment.” On this point, the Constitution — venerable document that it is — is ambiguous. Read one way, it could appear to say that after the President is impeached by the House, he loses the power to issue pardons. But read another way, it says that the President can issue pardons for criminal offenses but not for impeachment.
The latter reading is correct. There is no provision anywhere in the Constitution, statutes, or case law that strips a President of any power upon impeachment by the House (though of course, if convicted in the Senate, the President loses office and all of its powers). It would be anomalous for the President to lose only one power — the power to pardon — upon impeachment alone, and no serious legal authority has argued for this interpretation. Indeed, former President Bill Clinton issued many pardons after he was impeached in 1998.

Rather, the clause in Article II means that while a President can pardon an official (or any person) for a crime, he cannot pardon an official out of impeachment. In other words, the President does not have power to un-impeach. For example, if a federal judge committed bribery, the President could pardon the judge from a criminal bribery charge, but the President could not rescue the judge from impeachment. Indeed, no President has ever pardoned or even attempted to pardon an official from an impeachment.

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Greg (Colorado): Given that the Constitution grants the president the exclusive right to grant pardons for federal crimes, can a president reverse pardons issued by a prior president?

Probably not. The Constitutional pardon power is exceptionally broad: the President “shall have power to grant reprieves and pardons for offenses against the United States, except in cases of impeachment.”
There is no precedent for a court or Congress to overrule or reverse a Presidential pardon. At most, a President might, in certain narrow circumstances, be able to reverse his own pardon before it becomes official. In 2008, President George W. Bush pardoned convicted felon Isaac Toussie but then, upon learning that Toussie’s father had made large donations to Republican political groups, rescinded the pardon the very next day. Administration officials claimed the pardon had not yet been finalized because Toussie had not yet received formal notice of the pardon.
There is only limited and distant precedent for a President to revoke a prior President’s pardon. Former President Ulysses S. Grant revoked several pardons issued by his predecessor, former President Andrew Johnson, in some instances claiming (like Bush) that the pardons were not final because no formal notice had been made to the recipients. In the 140-plus years since Grant, no President has even attempted to rescind a pardon issued by a prior President.

Paul (California): Once Sen. Kamala Harris becomes vice president, how is her vacant Senate seat filled, and what happens in the interim if her absence gives Republicans a majority?

Under California law, the governor has the power to select a replacement for an empty Senate seat. California is among the majority of states — 37, to be precise — that fills vacancies immediately by gubernatorial appointment. In the other 13 states, the seat remains vacant until the state can hold a special election to fill the vacant seat.

The current governor, Gavin Newsom, is a Democrat, and is virtually certain to appoint a fellow Democrat to fill Harris’s seat. Given the narrow margin in the Senate (currently 50-48 in favor of Republicans, with two runoffs pending in Georgia), Newsom likely will be prepared to make his appointment immediately upon Harris’ resignation from her Senate seat to take the vice president position.

source: cnn.com