Stephen Colbert has tackled many important topics over the years, including the timely topic of immigration. Though his character Esteban Colberto is a bit culturally insensitive and controversial in its use of trite stereotypes, Colbert has looked at the topic from many angles.He's mocked Rand Paul from running from DREAMers, he's spoken to activists and he actually worked for a day in the fields as part of "Take Our Jobs" campaign, and then testified about the experience in Congress.