Witness intimidation? Organized crime? Investigate Trump, Cohen claims and threats Prosecutors and a grand jury should look into these serious claims of witness tampering and involvement with organized crime, and get to the truth.

David M. Dorsen | Opinion contributor

President Donald Trump and his lawyer, Rudy Giuliani, have been circulating vaguely sinister notions about Michael Cohen’s family — and Giuliani even suggested that Cohen's father-in-law "may have ties" to organized crime. Cohen and his lawyer, Lanny Davis, have countered by accusing Trump and Giuliani of obstructing justice and threatening and intimidating Cohen.

Cohen is an important witness in several venues, including investigations by Congress and special counsel Robert Mueller. But he postponed a Feb. 7 appearance before a House committee, citing “ongoing threats” to his family by Trump and Giuliani. The stakes could not be greater.

I urge the U S. Attorney for the Southern District of New York to open a grand jury investigation into both sets of allegations, if the office hasn't done so already. Because it is conducting investigations into various matters Trump, including his business dealings and Cohen activities such as hush money payments, it would not take long for this office to move.

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Both Trump and Cohen as well as their statements have a firm connection with New York and therefore are within the Southern District of New York jurisdiction. It seems federal crimes might have been committed. Finally, the allegations are not clearly directed at alleged collusion between Russia and the Trump campaign, so they are more attuned to the matters investigated by the SDNY.

The U.S. Attorney declined to comment for this column, both on the allegations and whether the office is conducting or contemplating an investigation. But as a former prosecutor in that office as well as a senior Senate investigator into misconduct in Watergate, I can make my proposal with confidence.

To start, the prosecutors or the FBI would interview Trump and Giuliani to find out whether there is a basis for the allegations they made. The absence of a factual and legal basis for their statements would be persuasive evidence of obstruction. Significantly, neither provided any specifics for their allegations.

Federal prosecutors need to get to the truth

But even if Trump and Giuliani did have evidence of criminal conduct, this would not end the matter. Unlawful threats can be based on truthful statements. The fact that Trump and Cohen chose to make their allegations publicly instead of in a communication to the Department of Justice is significant, especially since a president oversees DOJ.

There would also be the possibility that Trump, Giuliani and Cohen’s father-in-law were all at fault. While there is at present no evidence that Cohen’s father-in-law did anything wrong, a U.S. Attorney should not ignore allegations of criminal conduct. A grand jury composed of 23 ordinary citizens seems particularly well-suited to decide whether the Trump and Giuliani statements have the tendency to constitute threats and witness tampering. More than FBI agents and prosecutors, grand jurors would be good judges of the purpose and effect of those statements.

A lot is going on, including most recently Mueller's indictment of Trump confidant Roger Stone. None of that activity should prevent the premier U.S. Attorney’s office from getting to the bottom of these serious claims of witness tampering and involvement with organized crime.

David M. Dorsen, formerly assistant chief counsel of the Senate Watergate Committee and an assistant U.S. Attorney in the Southern District of New York, is the author of "The Unexpected Scalia: A Conservative Justice’s Liberal Opinions" and, most recently, "Moses v. Trump, a contemporary novel." Follow him on Twitter: @DavidDorsen