National Emergency or Executive Overreach?

On Friday, to avert another government shutdown, President Trump signed a bipartisan spending package that he argues did not include enough funding for a border wall. To secure that funding, he declared a national emergency. In advance of Trump’s official announcement, House Speaker Nancy Pelosi spoke out against the idea of an emergency declaration. Is declaring a national emergency in this situation allowed? Unprecedented? To get a better understanding of this use of executive power Amy Walter spoke to Dr. Barbara Perry, the director of presidential studies at the University of Virginia's Miller Center.