Tonight on The Last Word: Nancy Pelosi steps down from House Dem leadership. Also, Karen Bass becomes the first woman mayor of Los Angeles. Plus, Democrats blunt GOP dominance in state legislatures. And former prosecutors make the case for why the Justice Department has a "strong precedent" to indict Donald Trump over the Mar-a-Lago documents. Joy Reid, Rep. Eric Swalwell, Mayor-elect Karen Bass, fmr. Attorney General Eric Holder, Neal Katyal and Rep.-elect Maxwell Alejandro Frost join Lawrence O'Donnell.