According the documents released by Senators Grassley and Graham, former FBI director James Comey wrote the letter to not recommend criminal charges against Hilary in late April or May, months before he announced it on July 6, 2016.

This explains the lack of a real criminal investigation, or "matter" per Obama attorney general Lynch, which would have included a grand jury, subpoenas, and questioning Hillary under oath.

This may also explain why Bill Clinton met Lynch at the airport.  Lynch must have told Bill to relax, that there would be no indictment, and so they talked about golf and grandchildren.  Maybe for once Bubba was telling the truth.

We now know that the investigation was a sham from beginning to end.  Obama announced October 15, 2015 that Hillary did not commit any crimes, thus giving Lynch and Comey their marching orders:

I can tell you that this is not a situation in which America's national security was endangered. We don't get an impression that here there was purposely efforts to hide something or to squirrel away information.

She made a mistake. She has acknowledged it, And I think she'd be the first to acknowledge that maybe she could have handled the original decision better and the disclosures more quickly.

It was improper and unethical for Obama, as head of the Executive Branch of the government, to prejudge the investigation by the FBI and announce what the result should and would be.

Comey testified on June 8, 2017 that he felt pressured by Attorney General Lynch:

The attorney general had directed me not to call it an investigation, but instead to call it a matter, which confused me and concerned me[.] ... That was one of the bricks in the load that led me to conclude, "I have to step away from the department if we're to close this case credibly."

The Democrats and Destroy Trump Media are obsessed with the phony claim of "Russia collusion" while the real crime is the whitewash of the investigation of the Hillary email scandal.  Comey testified he was pressured by Lynch, yet he decided months before July not to recommend indictment.

It was the job of the attorney general to decide on indictment, not Comey.  Comey was to do a full investigation, which he obviously did not do, and turn the findings to the attorney general.  Of course, in this case, it would not have mattered, because Lynch would not have indicted Hillary.

If Comey did not trust the attorney general, then he should have informed the president and attorney general and Judiciary Committee that Lynch interfered with his election and requested an independent special counsel to decide the Hillary "matter."

Comey just does not make any sense.  First he decided in April 2016 to not recommend indictment.   Then he outlined on July 6, 2016 the facts that warranted an indictment, which he declined to recommend.  Next he reopened the "matter" in October, near the election date.  Then he testified on June 8, 2017 that Lynch had pressured him. 

Worse, on June 8, 2017, Comey admitted he leaked an FBI memo to his friend to leak it to the N.Y. Times.  This leak is a probable criminal violation.  According to George Washington Law School professor Jonathan Turley, a constitutional law expert:

The admission of leaking the memos is problematic given the overall controversy involving leakers undermining the Administration. Indeed, it creates a curious scene of a former director leaking material against the President after the President repeatedly asked him to crack down on leakers.

Besides being subject to Nondisclosure Agreements, Comey falls under federal laws governing the disclosure of classified and non-classified information.  Assuming that the memos were not classified (though it seems odd that it would not be classified even on the confidential level), there is 18 U.S.C. § 641 which makes it a crime to steal, sell, or convey "any record, voucher, money, or thing of value of the United States or of any department or agency thereof.

The Comey "matter" demands a full investigation.

Mueller is wasting time and expense chasing the Russia collusion.  He should conclude immediately that there was no collusion by Trump.  The assistant attorney general, Rosenstein, should pull the plug on this waste and appoint a special counsel to investigate the "investigation or matter" of the Hillary email scandal.

A special counsel is necessary to investigate the Hillary investigation-matter with the focus on Obama, Lynch, and Comey.