Does the Mueller Report Contain the Evidence for the Impeachment of Donald Trump?

The report of Special Counsel Robert Mueller has been completed, but not released publicly.  All we have is a letter from Attorney General William Barr stating that Mr. Mueller concluded the evidence he had accumulated of Donald Trump and members of his administration possibly conspiring with Russians to interfere in the 2016 elections was insufficient to justify criminal charges.  Barr's letter also said that Mueller could not decide whether President Trump or others had obstructed justice but that Barr had concluded they had not.

A storm of controversy has arisen over the fact that the report itself is not public and therefore neither Congress nor the public can evaluate Mueller's evidence for themselves.  Whether or not the report will be released in full remains to be seen.  But the delay in releasing the report leaves open the question whether the report contains enough evidence to warrant the impeachment of President Trump.

Criminal charges need to be proved beyond any reasonable doubt.  That is the standard ("burden of proof" is the legal term) that Mr. Mueller would have been working with when he, according to Barr, decided that criminal charges for conspiracy with Russians could not be proven.  That would have also been the standard Mr. Barr worked with when he decided that obstruction of justice charges were not warranted.  But the Constitution does not specify any particular burden of proof for impeachment.

The impeachment process contains two stages.  The first is impeachment--or, the leveling of charges--by the House of Representatives.  The House decides whether there is enough evidence to level charges against the President.  Grand juries in America can level charges (by issuing an indictment) when they believe there is probable cause to believe that the defendant committed a crime.  Probable cause is a much lower standard than beyond a reasonable doubt.  Based on what's already been publicized about possible Trump collusion with Russia, it seems quite possible that the Mueller report contains enough evidence to support a determination of probable cause.  So impeachment by the House could be a distinct possibility if the House chose to use the probable cause standard (and nothing in the Constitution prevents it from doing so).

The second stage of the impeachment process is a trial in the Senate.  The Constitution provides, in Section 4 of Article II that "The President, Vice President and all civil Officers of the United States, shall be removed from office on Impeachment for, and Conviction of, Treason, Bribery or other high Crimes and Misdemeanors."  One might argue that the word "Conviction" implies the reasonable doubt standard.  However, the reasonable doubt standard had only begun to find its way into English law in the 1780's, when the Constitution was written, and was not explicitly recognized by the U.S. Supreme Court until 1881 (see Miles v. U.S., 103 U.S. 304 (1881).  Thus, the Senate is not bound by the reasonable doubt standard, and could impeach President Trump because it believes that grounds for impeachment have been proven by, for example, a preponderance of the evidence or by clear and convincing evidence, both of which are lower burdens of proof used in different types of civil court cases.

It's been reported in the press that the Mueller report is lengthy and detailed.  Thus, it surely must contain a great deal of evidence.  Because of the possibility that the Mueller Report may contain enough evidence to support the impeachment and removal from office of President Trump, it is imperative for America's democracy that the full report be immediately released to Congress and the public.