NYT: Uvalde police waited to confront gunman knowing there were injured people in classrooms

Tonight on the Last Word: New reporting details a “cascade of failures” by Uvalde police during the elementary school shooting. Also, The Washington Post reports that Ginni Thomas pushed for Arizona lawmakers to overturn election results. Plus, how the January 6th hearings might inform the investigation into Donald Trump’s election interference in Georgia. And March for Our Lives plans to hold nationwide protests against gun violence this weekend. J. David Goodman, Barry Berke, Gwen Keyes Fleming and David Hogg join Lawrence O’Donnell.