Elizabeth Warren is the Democratic counterpart to Ted Cruz: a huckster politician who is only interested in grandstanding to bolster her public profile. She knows exactly why Wells Fargo’s CEO isn’t being criminally investigated.
Oh, and by the way, only the Justice Department can bring criminal charges. SEC is civil only, which has an absurdly lower burden of proof in order to find legal liability. And the SEC isn’t even going to probe Stumpf because they know that even under the basis of preponderance of evidence, they won’t find anything which suggests that Stumpf advocated for the perpetration of fraud and forgery.
Congressional hearings are all about grandstanding. It’s a way for politicians to score cheap points. Maybe you felt the same way when House Republicans repeatedly subpoenaed Clinton over her emails, Benghazi, etc. It’s a political circus.