DoJ isn't "independent" of the President. AG is chosen by the President, with, I'm sure, plenty of winks and nods
The Dems not pursuing Trash and his mafiya is a gold-plated invitation, closely watched by the Repugs, for the next Repug asshole President to go even further than Trash did, knowing he would unstoppable and unaccountable.
The lawless, anti-American Repugs and their Capitalist paymasters have had a strategy of making USA a permanent, one-party, authoritarian country. They are getting close every election.