Yes, the Mueller Investigation Has Obstructed Justice

The people who talk about obstruction of justice in Robert Mueller's investigation appear unaware that in the United States the prosecution can be guilty of obstruction of justice. 

Most people don't understand that the Bill of Rights provisions regulating law enforcement were added to the Constitution to prevent corrupt law enforcement agencies from misusing the criminal justice system to harass political activists.   One of the worst abuses in British legal history was  the "Star Chamber" proceeding which allowed the use of secret unsubstantiated allegations against the accused, especially political activists.

The involvement of British intelligence agent Christopher Steele in the investigation in effect makes it a form of Star Chamber proceeding.  I know he says he's retired, but think about it. Obviously,  if he's on a "secret mission" for the British government, he's not going to say "I'm on a secret mission to discredit Donald Trump."  He's going to say "I'm retired."   I have enough respect for Britain's MI6
to believe that it can  arrange  for agents on secret assignments to appear to have "jobs"  that have no connection to the British government. 

American courts need to know how information is obtained,    Agents like Steele need to keep some information and sources of information secret.  Courts need to know the truth. Agents must be able to lie convincingly such as when the British  overstated the status of Iraq's  Weapons of Mass Destruction.  

Regardless of whether or not  Steele  prepared the Trump dossier on assignment for his government, the dossier appears to be the type of propaganda piece an agent might prepare for his government. It's not important whether Steele's document caused the Mueller investigation or merely encouraged it.   What is important is that allowing a foreign agent to encourage a criminal investigation of an American politician allows other countries to meddle in our politics by providing evidence to destroy politicians they don't like.

Consider a hypothetical situation that could have occurred before the 2016 election.   A country wishing  to hurt Hillary Clinton might have secretly provided incriminating emails to Wikileaks.  Any country that has Hillary emails won't want our government to know it has emails with information about American procedures, personnel and goals so emails would have to be distributed secretly.   What if such emails indicated Hillary had worked out a deal with Britain to have Americans stay in Benghazi to protect equipment the British left behind when a terrorist attack caused them to  evacuate the area in exchange for something like a contribution to the Clinton Foundation or unspecified help if Hillary ran for president?  The emails could not have been used to start a criminal investigation because government could not have verified  that the documents were authentic unaltered emails which had been obtained in accordance with American laws. 

Now that I think about it, if Russia had been really anxious to elect Trump wouldn't it have  tried to secretly distribute real or fake Clinton emails?