In this weekly column "Cross-exam," Elie Honig, a CNN legal analyst and former federal and state prosecutor, gives his take on the latest legal news. Post your questions below. The views expressed in this commentary are his own. View more opinion on CNN. Watch Honig answer reader questions on "CNN Newsroom with Ana Cabrera" at 5:40 p.m. ET Sundays.

(CNN) As the Ukraine scandal spirals into an existential threat to his presidency, President Donald Trump and his defenders have gone into attack mode, scrambling to their battle stations and opening fire on seemingly anything that moves.

Their first target: the intelligence community whistleblower who reported information through established legal channels about Trump's efforts to persuade Ukrainian President Volodymyr Zelensky to investigate former Vice President Joe Biden and his son Hunter. These attacks on the whistleblower are flatly wrong and wildly dangerous, and the motives are transparent: Trump and his defenders assail the messenger because they know they are cooked on the actual message.

Trump and his loyalists have argued that the whistleblower offers only secondhand , hearsay information. Indeed, the whistleblower himself states in the complaint that he "was not a direct witness to most of the events described," and obtained information primarily from his intelligence community colleagues.

But the fact that the whistleblower's information is (by his own account) secondhand does not render it unreliable. On the contrary, the whistleblower's complaint has been largely corroborated -- including by Trump's own appointed Intelligence Community inspector general , who found it credible and of "urgent concern."

The whistleblower's complaint describes the substance of the critical July 25 Trump-Zelensky phone call accurately and in detail; it matches the rough transcript released by the White House. And the complaint correctly reports that the Trump White House improperly tried to "lock down" records of the call by storing them on "a separate electronic system that is otherwise used to store and handle classified information of an especially sensitive nature."

If the whistleblower was making things up, then how on earth would he have known accurately and in detail about the call itself -- and about the White House's internal effort to hide it? Trump and his defenders don't have an answer to that question.

But here's the thing: It doesn't matter. This scandal is not about the whistleblower and his complaint; it's about the evidence underlying the complaint, most importantly the White House's summary transcript of Trump's call with Zelensky. That conversation is damning to Trump -- it's potential evidence of federal crimes and abuse of power -- and reads precisely as the whistleblower described it.

It's not the whistleblower's complaint Trump should worry about; it's Trump's own words.

Making matters worse, Trump has unleashed an irresponsible, dangerous torrent of threats about the whistleblower. Trump has claimed that the person or people who gave information to the whistleblower are "close to a spy" and longingly noted that "in the old days ... we used to handle it a little differently than we do now" -- referring, not so obliquely, to executing disloyal spies.

To be clear: The President of the United States has publicly suggested punishment, up to and including execution, for members of our own intelligence community who provide information about potential wrongdoing through established, lawful channels.

Trump subsequently lashed out at the whistleblower on Twitter like a schoolyard bully challenging someone to "say it to my face": "I deserve to meet my accuser," Trump tweeted.

On this score, Trump is actually more or less correct. Our Constitution does afford every criminal defendant the right to confront witnesses against them in court, so if Trump is eventually charged criminally after he leaves office, he might well get the chance to meet his accuser face-to-face.

Even before then, Trump might face an impeachment trial in the Senate. If that happens, he'd almost certainly have the right to be present, and could have his longed-for showdown with the whistleblower then. Don't count on it though; I'm taking bets the President won't show at all if and when the Senate puts him on trial.

Trump has every right to defend himself vigorously. But he also has an obligation to do so responsibly.

Distortions of the truth, and not-so-veiled threats against witnesses, undermine our constitutional process as a legal matter and will ultimately backfire on Trump as a tactical one.

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