Has Mueller eaten from the 'fruit of the poisonous tree'?

There's been no such thing as a "down week" in legal news lately. Just as one story develops, it takes a turn, or another story comes along and pushes it to the side. In a dizzying two-day stretch, we went from a BuzzFeed report that President Donald Trump instructed his former attorney Michael Cohen to lie to Congress (which CNN and other news outlets could not confirm); to a public statement from the office of special counsel Robert Mueller refuting aspects of the BuzzFeed report; to BuzzFeed standing by its reporting and seeking clarification about Mueller's points of contention.

Prosecutors deal with this kind of situation frequently: two parties say two things that are simply not reconcilable. So, let's break it down. We know for sure that Michael Cohen lied to Congress about the Trump Tower Moscow project, and that he told that lie not as a lone wolf but rather -- to quote Mueller -- after going through a process of "preparing and circulating" his responses to others. Which leaves us with the following questions: (1) Who were those other people, (2) was Trump among them, and (3) if Trump was involved, how clear and how direct was his involvement?

Mueller's public refutation of BuzzFeed appears to indicate that Trump did not sit Cohen down and directly instruct him to lie. But, even short of that, there is still plenty that Trump could have done to make him criminally liable for Cohen's false testimony. (Though, at this point, we don't know what, if anything, Trump did.) That issue -- how much would Trump have to have said to Cohen to make Trump liable for perjury or obstruction? -- was the most commonly asked question this week. Read on for my answer below.

We also saw more self-defeating rhetoric from Rudy Giuliani, who asked Jake Tapper, "So what?" if the President might have spoken to Cohen about Cohen's false testimony to Congress. Giuliani then walked it back, claiming that Trump actually never spoke to Cohen at all about the testimony. He also said the Trump Organization might still have been pursuing the Moscow project as late as November 2016, and then, once again, tried to correct himself the next day. (Note to Giuliani: when you move the goalposts for your own kicker, you're supposed to move them closer in, not farther out).

As this all plays out, we prepare to hear again from Paul Manafort, who is in court on Friday for a hearing on the continuing dispute about whether he lied to Mueller's team. Cohen still intends to testify before Congress on February 7, though his attorneys have announced that he will not address any topics currently under investigation but rather will only tell "personal anecdotes" about his dealings with Trump. And Acting Attorney General Matthew Whitaker will testify in the House the next day, February 8. House Judiciary Committee Chair Jerrold Nadler sent a letter making clear he will grill Whitaker on anything and everything to do with Trump's potential interference in ongoing criminal probes.

Now, your questions

Gabi: If Trump asked Cohen what his testimony would be, saw or heard it would be a lie, and said "good," is that directing him to lie?

I once prosecuted a mafia case against a powerful Gambino family captain for conspiracy to murder his own nephew, who was suspected by the mafia (correctly) of cooperating with the FBI. The family sent a lower-level soldier to tell the captain that his nephew was a "rat," in an effort to get the captain's approval to commit the murder. The captain responded by asking if the soldier was absolutely sure the nephew was a "rat," and the soldier confirmed that he was. The captain said nothing more, and the murder happened soon thereafter.

This story illustrates that one of the toughest things about prosecuting the mafia -- or any secretive, corrupt enterprise -- is that a leader often doesn't have to give direct orders for his will to be known and followed. In my case, the captain never said, "kill him." Simply asking the question, "Are you sure he's a rat?," receiving the affirmative response and then saying nothing further made the captain's will clear: he blessed the murder, enabling it to happen.

Michael Cohen was Donald Trump's perfect apprentice

On one hand, as a legal matter, it was enough to charge a murder conspiracy; on the other hand, we knew our case would be exceedingly difficult to prove to a jury, so we gave the captain a plea deal for only five years (a deal I still question myself about to this day).

The key legal concepts here are (1) conspiracy and (2) aiding and abetting. Conspiracy is a broad concept that essentially makes it a crime for two or more people to agree to commit a crime; the agreement itself is the crime. A conspiracy does not need to be spoken out loud or explicit. It is enough if a prosecutor can prove a meeting of the minds. Of course, the less explicit the agreement, the harder it can be to prove. Aiding and abetting is another broad legal concept that makes it a crime to encourage, counsel or command another person to commit a crime. Again, even subtle or seemingly minor encouragement can fit the bill.

So, it will come down to the details. If Trump said, "Michael, I need you to lie for me," then Trump is clearly guilty. If Trump said, "Hey Michael, we're all sticking together on this one, so let's remember this Moscow thing ended in January," then I still see a chargeable (albeit more difficult) case against Trump. If Trump said, "Michael you're a good person and loyal and I'll leave it to you to do the right thing," then we are in a difficult gray area. And all of this gets even more complex if Trump got word to Cohen indirectly, through some third person. This is the type of fact-intensive determination that ultimately falls to a jury in a criminal trial, or to Congress when considering impeachment.

Of course, there are countless potential gradations here. But the beauty of our legal system is, for all the complex terminology and procedure, it often comes down to common sense: what would a normal person -- a juror in a trial -- understand this to mean? Ultimately, Mueller (and perhaps Congress) will need to make that decision, and every detail will matter.

Bob: Should Mueller decide to subpoena Trump, does Whitaker or the [new] AG need to approve it? Can Whitaker or [Barr, the likely next AG] block Mueller's efforts to interview the President?

Yes. Under the special counsel regulations, the attorney general can review "any investigative or prosecutorial step" -- a subpoena to the President certainly would qualify -- and the AG then may override the decision if he finds it "inappropriate or unwarranted under established Departmental practices."

But here's the kicker: if that happens -- if Mueller wants to subpoena the President, but the AG overrules him, then the AG must eventually notify Congress, "with an explanation" of the decision to override. So, if this happens, then Congress, and presumably the American public, eventually will learn about it.

Nick: Your statement that Justice Department policy is that a sitting president cannot be indicted sounds ludicrous! What if the President committed murder? He could still not be indicted? If that's true, it makes no sense whatsoever.

You've hit on one of the major objections to the current Department of Justice policy: how could we tolerate a murderer sitting in the Oval Office? In that extreme example, (It sounds crazy but then-Vice President Dick Cheney once accidentally shot a man in the face. The man survived, and Cheney was never charged with a crime) one answer is that the President can be impeached, removed from office and then immediately indicted. Or, failing that -- if, say, there was insufficient political will to impeach -- the President could be indicted and arrested on his first day out of office. (Unless, of course, he pardoned himself, which is a whole different constitutional dilemma).

Kenneth: Can [Trump's] tweets be used against him in a court of law? Assuming he ever has to appear in court to defend himself.

Absolutely. One of the fundamental features of our justice system is that a defendant's own statements are admissible in evidence at trial and can be used against him (hence the famous warning that you see on the cop shows: "Anything you say can and will be used against you in a court of law...") Trump's tweets and other public statements can be used to prove his state of mind, which can be the most difficult part of any prosecution -- proving not only what the person did, but why he did it. Judges often instruct juries that science has not yet developed a way to look inside a person's mind. True, but in the case of Trump, Twitter is darn close. One of the Trump defense team's biggest tactical blunders was not simply taking away his phone on day one.

Heidi: I would like to know if there is a way to use candidate Trump's words in July 2016, when he was on the campaign trail, and said "Russia, if you're listening, I hope you're able to find the 30,000 emails that are missing" to prove collusion?

Sure. The trick here would be showing how serious Trump was when he said this. A prosecutor might argue that this statement shows Trump knew the Russians were hacking and actively encouraged them to do so. If a prosecutor uncovered a secret e-mail from Trump to Russian intelligence (putting aside the fact that Trump doesn't use email) saying the same thing, you'd have powerful evidence of conspiracy to hack.

But both Trump and his defenders likely would counter that his statement was a joke, or mere political rhetoric, not actually intended to conspire with Russia. If he was going to conspire with Russia, they would ask, why would he do it out in the open for the whole world to see? Ultimately, this is the kind of evidence that would go to the Senate in the case of impeachment or a jury, which would have to use its common sense to decide.

Brian: If the impetus of this investigation of the President, as it pertains to collusion, was generated by opposition research by his opponent in the 2016 election and is false, misleading and improperly vetted, how can any of it be used as evidence?

I assume you're referring to the Steele dossier -- the report compiled by a former British intelligence officer in 2016 that outlined Trump's alleged entanglements with Russia. It is hotly disputed whether and to what extent the Steele dossier was correct or incorrect, but let's assume for this exercise that it was a complete fraud. Then we'd be looking at a legal concept called "fruit of the poisonous tree." If something improper happens in an investigation, then how much did that impropriety taint the evidence that was uncovered afterward?

For example, if a prosecution team obtained a search warrant for a house, and the search yielded a kilogram of cocaine, but it turned out the application for the search warrant contained false information, then the evidence (the "fruit," if you will) likely would be thrown out because it was discovered as a result of a flawed process (the "poisonous tree").

But the "fruit of the poisonous tree" doctrine is carefully limited. It does not extend forever. It does not apply to evidence that is too "attenuated" -- meaning too distant from the original problem -- and it does not apply to evidence that was discovered independently, or to evidence that would have been discovered anyway.

So, even if the Steele dossier was flawed or incorrect, it only would nullify evidence that was discovered directly as a result. It would not knock out everything that followed. To put it in non-legal terms: What the heck does the Steele dossier have to do with all the other facts that were discovered by Mueller way later and completely independently?

Mansour: What does it take to pass a constitutional amendment prohibiting federal government shutdowns?

The constitutional amendment process is enormously difficult, by design. A proposed amendment must be approved by a two-thirds majority in both the Senate and the House of Representatives. As if that wasn't a steep enough hill, the amendment also must be approved by three-fourths of the states (38 out of 50). There have only been 27 amendments in history. The most recent one was ratified in 1992, requiring that any raise in pay for Congress not take effect until after the next Congress has been elected.

There aren't any amendments particularly near passage right now. The closest one is the Equal Rights Amendment, which would require legal equity between men and women. The bill passed both houses of Congress in 1972, and 37 states have ratified it, though five of those states later rescinded their ratification, and legal questions remain about whether the deadline for approval has passed given that Congress approved the measure 47 years ago. While the current shutdown is the longest in history and has felt endless, it certainly will be resolved through political means well before an amendment could pass.

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