Congress should absolutely question FBI Director Jim Comey about why he chose not to bring charges against Hillary Clinton. Comey called her "extremely careless" and stated that someone in her position should have known better. He also implied that there was evidence that she violated statues, and then went on to say that no reasonable prosecutor would move forward with the case. Why shouldn't a jury decide if she's guilty?
Yes, I think that Comey should be investigated for not referring Hillary Clinton for charges. After he announced his decision, he then spent the bulk of his speech talking about exactly how she had violated multiple federal laws. An investigation could possibly get to the bottom of who may have influenced or pressured him.
Continuing to probe into what was likely a very stupid mistake is wasteful and is costing the taxpayers money. It is not in anyone's best interest for congress to do this and is likely politically motivated. If it was not an election year, it is likely that this story would not be getting so much attention.
Congress should be investigating the Director of the FBI after Hillary Clinton's non-indictment because he all but made the case for an indictment. Basically, what he said is ignorance is an excuse. So, once again a Clinton gets away with extremely questionable behavior. And the press will let this one slide by as it does with all democrats.