Where Mueller found the most evidence of Trump obstruction

In the Mueller report's second volume, the special counsel lays out 10 incidents of potential obstruction of justice by President Trump. In each, Mueller identifies the obstructive action, what it obstructed and what the president’s intent was in performing it. In some cases, he found “substantial evidence” of obstruction, but in others, none. Lisa Desjardins and William Brangham report.