Seditious conspiracy. The term – with its overtones of violent overthrow of government – connotes extreme gravity. It is one of the least employed charges in the United States criminal code. The Department of Justice has brought a seditious conspiracy case just twice in recent history. It won one of the cases, but the most recent ended in a humiliating dismissal.

So it was arresting when the former head of the government’s Jan. 6 investigation, Michael Sherwin, told a “60 Minutes” interviewer that he personally believed that “the facts do support those charges” for some of the Capitol attackers, and “as we go forward, more facts will support that.”

Sherwin was appointed to lead the investigation by former Attorney General William Barr; he resigned on March 3, as Merrick Garland took over the department. Now it is Garland’s task to make the delicate and consequential decisions about whether seditious conspiracy fits the events of Jan. 6.

The statute and its predecessors have a checkered, indeed infamous, history. The Sedition Act of 1798 punished “false scandalous and malicious writing” about the president or Congress. A version passed during World War II made it a crime to teach the desirability of overthrowing the government and led to the unconstitutional harassment of American Communist Party members. Those prosecutions survive now as examples of a shameful suppression of free speech.

The current statute, however, is not John Adams’ or FDR’s sedition. It contains a number of definitions for seditious conspiracy, including this: If two or more persons “conspire … by force to hinder or delay the execution of any law of the United States … they shall be fined … or imprisoned … or both.”

Those elements would appear to fit the actions of the worst Jan. 6 offenders like a glove. The point of storming the Capitol was to hinder or delay Congress’ legal duty to certify the election of Joe Biden to the presidency.

But as close a fit as the words appear to be, Garland and company have a number of consequential issues to consider. To bring the sedition charge and lose would be a spectacular defeat in one of the most important federal investigations in the history of the Department of Justice.

One issue related to proving conspiracy – there must be actual agreement among the conspirators about their actions, though case law has shown it needn’t be express or explicit. It was a failure to prove conspiracy that did in the government’s last sedition case, in 2010. The judge wasn’t convinced that radical Christian militia members in Michigan had formed real plans to launch attacks.

Actually launching an attack is another element the department will take into account. The most egregious sedition prosecutions in U.S. history were brought against speech alone, political agitators whose plans never came to fruition. On Jan. 6, the nation watched in real time as the Capitol was breached, police officers attacked, the House chamber evacuated. The mob moved far beyond speech, a fact that should eliminate concerns that a sedition charge is unconstitutional.

Another crucial calculation Garland must make: Would a sedition indictment, with all its implications, constitute prosecutorial overreach? Is it unjust, and could it run headlong into a skeptical judge or jury?

In 1993, the government successfully prosecuted Omar Abdel Rahman – known as the blind sheik – and nine others associated with the 1993 World Trade Center bombing on seditious conspiracy charges. The evidence showed the group planning to blow up, among other New York sites, the U.N., the George Washington Bridge, and the Lincoln and Holland tunnels. They represented a massive threat to the city and the nation, and Abdel Rahman was sentenced to life in prison.

Does invading the Capitol and attempting by force to shut down the workings of the republic measure up? The seditious conspiracy statute can apply to different factual scenarios. The events of Jan. 6 fit, even if the sentencing needn’t go as far as the blind sheik’s.

After Sherwin’s “60 Minutes” interview aired, the Justice Department quickly referred his comments to the Office of Professional Responsibility. As a former federal prosecutor, I can attest to their impropriety; investigations must remain confidential until indictments are delivered. Sherwin’s parading of his subjective views could steal the department’s thunder when it announces its charges or make it appear timid if seditious conspiracy isn’t what makes the final cut.

Nonetheless, from all we’ve seen (and the investigators know much more), Sherwin’s assessment is probably correct. Some protestors came to Washington in January to peacefully express their support for a president they thought had been robbed. Some came disposed to fulfill Donald Trump’s “it will be wild” prophecy. And others no doubt were masterminds and marauders resolved from the start to impede the lawful transfer of power by whatever means necessary.

We should call such a group what they are: seditionists. So should the Department of Justice.

Harry Litman is a former U.S. attorney and the host of the podcast “Talking Feds.” Twitter: @Harry Litman