 Well, the Trump campaign has been drumming up anti-immigrant sentiment for months. And more than half of Americans think undocumented immigration is a critical threat. But there's a lot of data that shows that undocumented immigrants do not commit more crimes. In fact, they commit less. We simply are not in the midst of an immigrant crime wave. So to the promises that Donald Trump made last night, one of the things he said was mass deportations. What would that mean?