Tonight on The Last Word: Appeals court judges are skeptical of Trump attorneys' claims in court. Also, top House Democrats usher in a new generation of leaders. Plus, Colorado Springs mourns for the five people killed in the Club Q shooting. And the Cherokee Nation pushes to seat a delegate in Congress. Andrew Weissmann, Rep.-elect Daniel Goldman, Colorado Gov. Jared Polis, Rep. James Clyburn and Cherokee Nation Delegate-designate Kim Teehee join Lawrence O'Donnell.