Stephen Colbert was last night's guest on "The Late Show," where he chatted with David Letterman about his testimony to Congress last month on the subject of undocumented field laborers.

Colbert acknowledged the critics who asked why he was allowed to testify by making fun of it himself. Letterman broke the ice by asking if "anybody with a TV show [can] go down and testify?"

"Evidently," Colbert said. "Because I had very little other qualifications."

Colbert also talked about his conversation with Zoe Lofgren, the Congresswoman who asked Colbert to testify after he worked for a day on a farm with illegal immigrants. He joked about her request to have him testify, asking if he should and wondering if people would "go apesh*t." Indeed, they did.

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