Caroline Polisi is a federal and white collar criminal defense attorney in New York. She frequently appears on CNN as a legal analyst and is an anchor at the Law & Crime network, providing live legal analysis on high-profile court cases. The views expressed in this commentary are her own.

(CNN) "You fight back, oh, it's obstruction," President Donald Trump has told the press about his attempts to push back against what he views as a meritless investigation into whether his presidential campaign had inappropriate contacts with Russians. Now amid reports that Trump's legal team is actively negotiating the terms of an in-person interview with special counsel Robert Mueller on the Russia probe comes the latest revelation that he allegedly ordered White House counsel Don McGahn to fire Mueller in June. The President has denied the reports.

Caroline Polisi

While it is tempting to view this recent development as slam-dunk evidence of obstruction of justice, it cannot be analyzed in a vacuum. McGahn, who had been seen as a Trump loyalist, ultimately rebuffed the request to fire Mueller. And while perhaps nothing better illustrates the President's fundamental misunderstanding of the role of our executive branch than his conflation of obstruction with fighting back, he has displayed a dizzying and at times remarkable pattern of obstructionist behavior while in office.

Yet there is simply no way of measuring the practical merits of an obstruction of justice case (and yes, the President can obstruct justice, no matter what John Dowd, Trump's private lawyer, says ) without getting to the question of whether Mueller has uncovered any evidence of underlying criminal coordination in the form of, say, a conspiracy to violate campaign finance or anti-hacking laws between team Trump and the Russians.

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Could Mueller conclude that Trump obstructed justice? From a purely legal standpoint, based just on the facts as we know them today, the answer is yes. Highlights of an obstruction case against Trump include his asking then-FBI Director James Comey for a loyalty pledge and urging him to drop his investigation into former national security adviser Michael Flynn, plus his subsequent firing of Comey, citing the now infamous memo written by Deputy Attorney General Rod Rosenstein. The contents of that memo are now generally acknowledged to have been wildly a pretext since the President admitted the actual reason he fired Comey was, quite simply, "this Russia thing."

But the answer is yes only in theory. Practically speaking, without evidence of an underlying crime, any allegations of obstruction of justice will likely fall flat, for two reasons:

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