Story highlights Paul Callan: Potential obstruction of justice case against President Trump just took quantum leap in strength and legal sustainability

Dark clouds are gathering over the President and his new administration, Callan writes

Paul Callan is a CNN legal analyst, a former New York homicide prosecutor and currently is of counsel at the New York law firm of Edelman & Edelman PC, focusing on wrongful conviction and civil rights cases. Follow him on Twitter @paulcallan. The opinions expressed in this commentary are his own.

(CNN) On Friday the potential for an obstruction of justice case against President Donald Trump took a quantum leap in strength and legal sustainability when the New York Times reported that Trump had advised two of the investigation's targets that the Russia "pressure" was off and that Trump had fired FBI Director James Comey, who he described as a "nut."

It was shocking enough that the President had invited two of the targets of an ongoing FBI counter intelligence investigation -- Russian Foreign Minister Sergei Lavrov and Russian Ambassador to the U.S. Sergey Kislyak -- to a special Oval Office meeting May 10, just a day after firing Comey, and that he excluded the American press while including the Russian press, including a photographer.

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The meeting also triggered a major controversy when it was revealed that the President disclosed classified information to the two Russians in what seemed to be a spontaneous and careless manner (though Trump later asserted, correctly, that he has a right to declassify information as he sees fit).

But according to the Times report Friday, the President also advised Lavrov and Kislyak that:

"I just fired the head of the FBI. He was crazy, a real nut job." The Times account also noted that the President observed that "I faced great pressure because of Russia. That's taken off."

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