Updated April 17, 2024 at 4:09 PM ET

The U.S. Supreme Court appeared divided on Tuesday, with conservatives expressing various degrees of skepticism about the statute used to prosecute more than 350 people involved with the Jan. 6 riot at the Capitol.

At least partially on the line at Tuesday's argument was the Justice Department's effort to punish some of those it deems the more serious participants in the Capitol riot. Roughly one-quarter of those prosecuted so far for their roles in the Capitol invasion have been charged with violating a federal statute enacted after the Enron scandal in 2002, a scandal that involved massive document shredding and fraud.

One part of the law makes it a crime to "corruptly" alter or destroy documents and records related to an official proceeding. The second part makes it a crime to otherwise obstruct or impede an official proceeding, including a congressional proceeding.

Joseph Fischer, a former police officer charged in the riot, is challenging the use of the second provision, asserting that it was never meant, as the government claims, to be a catchall obstruction law.

His lawyer faced a grilling from the court's three liberal justices, Sonia Sotomayor, Elena Kagan and Ketanji Brown Jackson. Kagan suggested that, in her view, Congress wrote the second part of the law to "plug gaps" in the then-existing obstruction statutes. In short, as she put it, "It was meant to function as a backstop."

Jackson said that trying to prevent the electoral count seemed to her like an obstruction of an official proceeding. And Sotomayor said that if this statute doesn't seem to be an exact match for the Jan. 6 attack, that is because there had never been an event like this one before.

But Fischer's lawyer, Jeffrey Green, seemed to have a willing audience in the court's six conservative members. They aimed their most skeptical questions at Solicitor General Elizabeth Prelogar and her assertion that the statute was meant to be a broad obstruction provision.

Justice Clarence Thomas observed that there have been other violent protests that interfered with official proceedings. Have federal prosecutors "applied this provision to other protests in the past?" he asked.

Prelogar replied that the Justice Department has enforced the law, applying it in the past to cases that involved more than document destruction and evidence tampering.

Justice Neil Gorsuch asked whether "a sit-in that disrupts a trial or access to a federal courthouse qualify? Would a heckler in today's audience qualify or at the State of the Union address?"

Those actions would not meet the criteria of corruptly and intentionally violating this law, replied Prelogar.

Justice Samuel Alito followed up, posing this question: "Let's say that today while you're arguing, five people get up, and they shout either, 'Keep the Jan. 6 insurrectionists in jail,' or 'Free the Jan. 6 patriots.' And our police officers have to remove them forcibly" — would that be a violation of this statute?

"No," replied Prelogar, because the government doesn't think this statute picks up such "minimal" interferences with proceedings.

Justice Kagan interjected at this point, asking the solicitor general what sort of evidence the government typically presents in these Jan. 6 prosecutions. Prelogar replied that the government has to prove that the defendants specifically intended to disrupt the joint meeting of Congress where the electoral votes were to be counted.

"We have focused on things like preparation for violence, bringing tactical gear or paramilitary equipment to the Capitol," she said.

Prelogar added that prosecutors have brought charges against 1,350 defendants in connection with Jan. 6, but because of the need to show intent to prevent the counting of the electoral ballots, only about 350 of those defendants have been charged with obstruction.

Addressing the concern voiced by several justices that the penalty for violating this provision carries a maximum sentence of 20 years in prison, Prelogar said that the average sentence among the the individuals charged only with this obstruction statute is 26 months imprisonment, and the median has been 24 months. So, she contended, "There's no reasonable argument to be made that the statutory maximum here is driving anything with respect to sentencing."

Still, Chief Justice John Roberts remained doubtful, also probing whether the Justice Department has similarly applied this statute in other cases. Prelogar replied that there is a key difference between statutes that do not require an intent to obstruct and this one, which does have that proof of intent requirement.

That, however, didn't seem to allay the "concerns" of the remaining two conservative justices, Amy Coney Barrett and Brett Kavanaugh.

Kavanaugh noted there are six other counts in the indictment of the defendant in this case, including civil disorder and assault. "Why aren't those six counts good enough, just from the Justice Department's perspective, given that they don't have any hurdles?" he asked.

"Because those counts don't fully reflect the culpability of petitioner's conduct on Jan. 6," answered Prelogar. Fisher "had said in advance of Jan. 6 that he was prepared to storm the Capitol, prepared to use violence. He wanted to intimidate Congress. He said, 'They can't vote if they can't breathe.' And then he went to the Capitol on Jan. 6 with that intent in mind and took action, including assaulting a law enforcement officer."

If the court rules in favor of defendant Fischer, a number of the 350 people charged under the obstruction statute will likely have to be resentenced or released from prison. Indeed, some have already been conditionally released, pending the outcome of the case.

The obstruction section of the law is also the basis for at at least one, and arguably two, of the charges against Donald Trump in the election obstruction case currently pending against him in Washington, D.C. So, if the Supreme Court ultimately rules that both parts of the obstruction law are aimed at document and evidence manipulation, Trump's lawyers would almost certainly seek to have those counts dismissed.

Special counsel Jack Smith has indicated that regardless of how the Supreme Court rules in Tuesday's case, the charges against Trump would survive; because the former president is charged with creating slates of fake electors, Smith has said, that ties his conduct more firmly to both parts of the the obstruction statute.

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