 Sources telling ABC News that police suspect Crooks got on the roof not by using the five-foot ladder he may have recently purchased, but by climbing on top of an air conditioning unit. The Homeland Security Inspector General, meantime, has formally opened a probe into Trump's Secret Service security at that rally. President Biden campaigning in Nevada again today, trying to shore up support as calls grow for him to step aside as the nominee. ABC's Selena Wang says the president may also be shifting to support changes to the Supreme Court.