New York Sen. Charles Schumer recently declared: “Polarization and partisanship are a plague on American politics.” He says one of the main culprits is our party primary system. It is not a new criticism. Political scholars have long argued that when primary elections are restricted to voters from one party, nominees with the most extreme views often win. But some question whether open primaries – where voters can cross party lines — actually improve the electoral fortunes of moderate candidates. And others worry open primaries dilute a party’s ability to nominate their own candidate without outside interference. Diane and her guests discuss the role of primaries in today’s polarized politics.