I don't know why the attorneys representing the reported 37 people indicted by Special Counsel Mueller haven't challenged the law on behalf of their clients, considering the illegal FISA warrant.  Under the due process clause of the Fourteenth Amendment, the Supreme Court has enunciated the "fruit of the poisonous tree" doctrine, first in Nardone v. United States (1939) and later applied it in other cases, such as Mapp v. Ohio.  It generally holds that evidence that is the direct result or immediate product of illegal conduct on the part of an official is inadmissible in a criminal trial against the victim of the conduct or other person with standing.

Having stated that, as a long retired law enforcement officer in police and corrections, I recollect from my training and academy classes that if a warrant was false or tainted, all of the charges brought against someone would be thrown out under the fruit of the poisonous tree doctrine.

In Mueller's case, the phony report made up by British agent Christopher Steele that was used to get the FISA warrant to spy on Carter Page for colluding with Russia was in and of itself an illegal submission that would taint the reason for the investigation.

Disgraced former FBI director James Comey stated that the report is unverifiable, all the while colluding and conspiring with his cohorts to take down the president, which should tell all that the warrant was tainted right from the get-go.

In my day, in order to get a warrant, the rule was that "no warrant shall be issued but upon probable cause."  Probable cause stems from evidence compiled by the people seeking the warrant, which means that in the case of the FISA warrant, it was submitted without real evidence to justify the warrant, using a report of innuendo and falsehoods made up by people who were undermining the rights of an American citizen.

From my understanding of the doctrine, knowing there are exceptions, once the warrant was illegally obtained, any of the actions stemming from the investigation by Mueller isn't admissible, meaning all of the indictments that followed should be thrown out.  No one who was indicted would have been but for the warrant and investigation.

Having said that, I want to add that there were crimes committed that involved the Mueller investigation that were totally ignored.  Otherwise, we would have heard about it. 

Hillary Clinton and her ilk were responsible for getting the phony report through Fusion GPS.  She destroyed evidence and obstructed justice.  Comey stated as much in his interview before Congress and the news media.  What she and her co-conspirators did was unconscionable.

Graphic credit: Mike Youngson.