Knowing whether former President Trump’s conduct on Jan. 6 violated one or more criminal statutes is important for several reasons. First, the public should know whether Trump committed any crimes. Second, identifying potential crimes can shape what the House Select Committee investigates. Third, Trump’s potential criminality affects Congress’s ability to obtain information in the face of a claim of executive privilege. And finally, identifying likely crimes could determine whether the Justice Department pursues a criminal investigation and then prosecutes the former president.

Harvard Law Professor Laurence Tribe and former U.S. Attorneys Barbara McQuade and Joyce White Vance have presented “a roadmap for the Justice Department to follow in investigating” whether Trump’s efforts to overturn the 2020 presidential election were criminal. Acknowledging that the facts did not yet establish any crime beyond a reasonable doubt, they listed a half-dozen offenses they said merited investigation.

Jeffrey Toobin, CNN’s chief legal analyst, answered “not so fast.” Reviewing the offenses listed by Tribe, McQuade, and Vance, Toobin concluded, “[T]here is no basis to prosecute Trump and little reason even to open an investigation.”

Neither Tribe and his coauthors nor Toobin mentioned what may be the clearest case for prosecuting the former president. By violating his legal duty to do what he could to end the unlawful occupation of the Capitol, Trump became an accomplice to that crime. He is subject to the same punishment as the rioters who entered the building.

More than 575 of the 674 people charged in the Jan. 6 insurrection have been charged with unlawfully entering or remaining in a restricted building or grounds. This offense is usually a misdemeanor, but it becomes a felony punishable by as much as 10 years in prison when it results in significant bodily injury or when an offender uses or carries a dangerous weapon or firearm during the crime.

Failing to prevent a crime usually does not make someone an accomplice, but it is sufficient when this person had a legal duty to intervene. For this reason, a railroad conductor who failed to prevent passengers from transporting bootleg liquor was himself convicted of transporting the liquor. Similarly, a parent who made no effort to stop an assault on her child was guilty of the assault herself. And a police officer who arranges to be somewhere else at the time of a robbery aids and abets the robbery. This officer can be convicted along with the robbers at the scene.

The Constitution gave Trump a clear legal duty to intervene. Article II, Section 3 provides, “[The President] shall take Care that the Laws be faithfully executed.” This provision permits good-faith exercises of law-enforcement discretion, but a president unmistakably violates his duty when he refuses to enforce the law because he wants a crime to occur—when, for example, he hopes to advance his own interests through the criminal conduct of others. As abundant evidence shows, that’s what transpired on Jan. 6.

Trump’s ability to enforce the law was unique. Like other public officials, he could have sought the assistance of additional police officers or military forces, but, unlike anyone else in America, he had a less costly and probably more effective way to bring the crime to a halt: He could simply have asked his followers to stop.

More than three hours after the rioters violently entered the Capitol grounds and two hours after they forced their way into the building, Trump did post a video telling them to go home. But he resisted sending any cease-and-desist message earlier, thereby violating his duty to see the law enforced.

Trump had another legal duty—a duty apart from his duty to “take Care that the Laws be faithfully executed”—to do what he could to end the occupation. Even if his direction to march to the Capitol and “fight like hell” was not intended to start a riot, it led to violence and placed the Vice President and members of Congress in peril. A person who creates a physical danger—even innocently—has a legal duty to take reasonable measures to prevent injury from occurring. Someone who’s started a fire can’t just let it burn out of control.

Trump could not be convicted without proof of his criminal intent, but his desire for continued occupation of the Capitol seems clear. Why else did he fail for hours to ask his supporters to desist, and why, even then, did he tell these criminals “we love you” and “you’re very special”? And why, according to ABC News correspondent Jonathan Karl,  did the first takes of his message leave out a request to end the occupation, prompting his aides to request repeated do-overs?

A president unmistakably violates his duty when he refuses to enforce the law because he wants a crime to occur.

White House officials told a Republican senator that Trump was “delighted” when rioters pushed their way past police officers to enter the building. A close advisor to the President informed the Washington Post that “rather than appearing appalled, Trump was , , , enjoying the spectacle and encouraged to see his supporters fighting for him.” Officials told Kate Collins of CNN that Trump was “borderline enthusiastic because it meant the certification [of the election] was being derailed.” Trump booster Sen. Lindsey Graham observed, “The president saw [the rioters] as allies in his journey.”

Trump’s rebuffs of specific requests for assistance supply further proof of his intent. House Minority Leader Kevin McCarthy now refuses to confirm or deny it, but he told House members of Trump’s response to McCarthy’s urgent request for presidential action—“Well, Kevin, I guess these people are more upset about the election than you are.” Philip Rucker and Carol Leonnig reported  that Ivanka Trump urged her father repeatedly to ask the rioters to disperse, that White House Chief of Staff Mark Meadows and other White House staff encouraged her effort, and that Trump refused to take calls from advisors he knew would give him the same message. New York Times reporter Maggie Haberman wrote that “many aides believed Trump was pleased by what he was seeing . . . as he repeatedly refused requests to get him to say something clearly rejecting the violence.”

Second-hand reports of Trump’s behavior during the Jan. 6 occupation are inadmissible hearsay, but the House Select Committee can seek and require the testimony of people who observed Trump’s conduct and heard his remarks. A federal grand jury convened by the Justice Department should investigate Trump’s conduct as well.

Trump has instructed his former aides and unofficial advisors to resist the Select Committee’s subpoenas by claiming executive privilege. One, Steve Bannon, already has refused to appear, and the House has voted to hold him in contempt.

Failing to prevent a crime usually does not make someone an accomplice, but it is sufficient when this person had a legal duty to intervene.

The Supreme Court has recognized that executive privilege “survives the individual President’s tenure,” but when Congress seeks “important” information that cannot be obtained elsewhere, this privilege is unavailable. Moreover, although no court has ruled on the issue, executive privilege must be subject to the same “crime-fraud” exception as the privilege for confidential attorney-client communications. A client’s statement to a lawyer that he intends to go on committing a crime is not privileged.

To establish the “crime-fraud” exception, the committee would need to present a prima facie case that Trump engaged in criminal conduct. If the committee were to rely only on the crimes listed by Tribe, McQuade, and Vance, that showing might be difficult, but establishing a prima facie case that Trump unlawfully aided the occupation of the Capitol looks easy. A judicial determination of the former president’s criminality could come quickly (for example, in contempt-of-Congress proceedings), and with that determination, his invocation of executive privilege would have backfired.

Both the Select Committee and a federal grand jury should also investigate the serious crimes listed in Tribe, McQuade, and Vance’s roadmap. Although the Select Committee appears to be considering evidence of these offenses, there is no sign the Justice Department has begun an investigation.

The most serious of the crimes on the roadmap is inciting an insurrection, but, as the authors acknowledged, a court might rule that Trump’s remarks on Jan. 6 were protected by the First Amendment. That obstacle would disappear if the government sought to punish, not the incitement (or not just the incitement), but Trump’s refusal to enforce the law after the insurrection began. Even if Trump’s remarks could not be punished, they could be received in evidence as proof of his intent. Although his call to “fight like hell” initially might have seemed ambiguous, the ambiguity disappeared when Trump’s supporters invaded the building and he refused to call them off.

Trump surely must have intended at least the illegal occupation. In addition, his refusal to enforce the law would make him an accomplice to every other crime he sought to promote.

President Biden is said to have little appetite for prosecuting his predecessor, and Attorney General Garland may share the president’s concern that an attempt to send Trump to prison would polarize our nation even further. There is indeed reason for concern, but Biden could avoid imprisoning Trump and could move toward healing America by pardoning him and other Jan. 6 offenders after a conviction. Truth could precede forgiveness. Biden might follow the example of President Washington who, in the first U.S. pardons ever given, extended amnesty to participants in the Whiskey Rebellion and set aside the death sentences of two of its leaders.

The time to forgive Trump is not now, and the way to forgive him is not for the Justice Department to rule out prosecution from the outset. Far from desisting or repenting, Trump continues to praise the crime he aided and abetted. On Oct. 21, as the House asked the Justice Department to prosecute Steve Bannon for criminal contempt, Trump issued this “war is peace” proclamation: “The insurrection took place on . . . Election Day. Jan. 6 was the protest!” Prosecuting 674 foot soldiers while exempting their chief for political reasons would be disgraceful.

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