Obstruction Charge Takes Center Stage at Jan. 6 Court Hearing

Prosecutors and defense lawyers squared off on Monday at a federal appeals court hearing in Washington over the use of a criminal charge whose viability could affect the cases of hundreds of people indicted in connection with the Jan. 6, 2021, attack on the Capitol — and could help decide what, if any, charges could ultimately be brought against former President Donald J. Trump.

The charge at the center of the arguments before the U.S. Court of Appeals for the District of Columbia was the obstruction of an official proceeding before Congress.

The Justice Department has used the count in scores of Capitol riot cases to describe how a pro-Trump mob disrupted the central event on Jan. 6: the certification of the 2020 election that took place during a joint session of Congress.

Defense lawyers want the appeals court to rule that the count has been applied incorrectly by the Justice Department and dismiss it from all the Jan. 6 cases in which it has been charged.

The arguments presented at the 90-minute hearing, while highly technical, hit on a critical issue that has shaped the contours of the government’s vast investigation of Jan. 6. That issue was how prosecutors in hundreds of cases have decided between charging people with petty offenses like trespassing or disorderly conduct, which carry a maximum of six months in jail, or the much more serious obstruction count, which carries a maximum of 20 years in prison.

During the hearing, a prosecutor, James Pearce, argued in favor of the obstruction charge, saying that it had been properly applied in nearly 300 Jan. 6 criminal cases. The law requires proving that any interference with a congressional proceeding be done “corruptly,” and Mr. Pearce argued that in cases where the charge has been used, defendants committed other “corrupt” acts like destroying government property or assaulting police officers.

A defense lawyer, Nicholas D. Smith, countered that the obstruction charge had been wrongly applied and that its use in all of the Capitol riot cases should be struck down — even in those in which defendants have already pleaded guilty or been sentenced.

Mr. Smith claimed it was “an injustice” that the government had repeatedly used the obstruction charge instead of bringing a less serious charge like illegally parading at the Capitol.

If the three-member panel of the court finds in favor of the defense, it would be a devastating blow to the government’s attempts to hold the pro-Trump rioters who stormed the Capitol accountable for the attack. An adverse ruling would force prosecutors to scramble for a replacement charge or accept the lower sentences attached to lesser charges.

It could also have a crippling effect on the Justice Department’s investigation of Mr. Trump’s role in overturning the election.

Given that a federal judge in California and the House select committee investigating Jan. 6 have both said there is evidence that Mr. Trump is guilty of obstruction of Congress, legal experts have argued that if the former president is prosecuted in connection with Jan. 6, he is likely to face the obstruction count.

The charge — formally known in the penal code as 18 U.S.C. 1512(c)(2) — was never a perfect fit for the many cases stemming from the Capitol attack. It was passed into law as part of the 2002 Sarbanes-Oxley Act, which sought to clamp down on corporate malfeasance.

The measure was initially intended to prohibit things like shredding documents or tampering with witnesses in congressional inquiries. Defense lawyers in dozens of Capitol riot cases have challenged its applicability, arguing that prosecutors had stretched the statute beyond its scope and used it to criminalize behavior that too closely resembled protest protected by the First Amendment.

One judge on the appeals court panel, Gregory G. Katsas, appeared to agree with this argument. Judge Katsas, who was appointed by Mr. Trump, said the government’s interpretation of the law seemed to establish a “new conception of obstruction wholly divorced from evidence tampering.”

But another Trump-appointed member of the panel, Judge Justin R. Walker, left open the possibility that the government had used the charge properly. Judge Walker noted that while lesser charges have often been used to punish people who have demonstrated at other events at the Capitol, what happened on Jan. 6 could not be thought of as “normal protest.”

The third judge on the panel, Florence Y. Pan, appointed by President Biden, seemed to side with the government throughout the hearing.

Over the past year or so, 18 judges in Federal District Court in Washington have ruled that the obstruction charge was valid. Only one judge, Carl J. Nichols, has said its use in Jan. 6 cases was improper.

In three cases, Judge Nichols, who was also appointed by Mr. Trump, dismissed the obstruction count, reading the statute narrowly and saying that it could be used only if there was evidence that the obstruction in question had an effect on “a document, record or other object.”

The Justice Department appealed all three of Judge Nichols’s rulings to the circuit court in Washington. The cases included those of Joseph Fischer, a Pennsylvania police officer accused of pushing at law enforcement officers during the Capitol attack; Garret Miller, a Dallas man charged with storming the building and facing off with officers inside; and Edward Jacob Lang, a self-described social media influencer from New York who prosecutors say attacked the police with a baseball bat.

Thousands of pages of court filings suggest that prosecutors have not brought the obstruction charge willy-nilly, but have instead used it for defendants whose behavior seems to have gone beyond mere trespassing or disorderly conduct. The count has been used against defendants who broke into the Capitol during an early wave of the attack, who penetrated into a sensitive area of the building like the Senate floor or who were inside for long periods of time.

Still, a ruling by the appeals court striking down the charge would badly damage the cases against as many as 290 defendants who have been indicted on the obstruction count. It would also affect the cases of at least 70 people who have already been convicted of — or have pleaded guilty to — the count.

Among those are some prominent Jan. 6 rioters, like Jacob Chansley, also known as the QAnon Shaman, who was sentenced to 41 months in prison on the obstruction charge alone, and five members of the Oath Keepers militia who were found guilty of obstruction — and other charges, including sedition — last month.