We wade into the heated debate over immigrants' impact on the labor market. When the number of workers in a city increases, does that take away jobs from the people who already live and work there? Does a surge of immigration hurt their wages? The debate within the field of economics often centers on Nobel-prize winner David Card's ground-breaking paper, "The Impact of the Mariel Boatlift on the Miami Labor Market." Today on the show: the fight over that paper, and what it tells us about the debate over immigration. More Listening: - When The Boats Arrive) - The Men on the Roof)*This episode was hosted by Amanda Aronczyk and Jeff Guo. It was produced by Willa Rubin, edited by Annie Brown, and engineered by Valentina Rodríguez Sánchez. Fact-checking by Sierra Juarez. Alex Goldmark is Planet Money's executive producer.Help support Planet Money and hear our bonus episodes by subscribing to Planet Money+ in Apple Podcasts) or at plus.npr.org/planetmoney).*Learn more about sponsor message choices: podcastchoices.com/adchoices)NPR Privacy Policy)