On April 18, the Supreme Court heard oral arguments on the constitutionality of DAPA (Deferred Actions for Parents of Americans), President Obama's executive order that offers temporary legal status to undocumented parents of American children. The order will defer deportation proceedings against four to five million undocumented aliens and hand them temporary work permits. A ruling is expected in June.

Like much of the country, libertarians have been deeply divided over whether the president has the power to issue such an order. Those who defend him argue that he has broad prosecutorial authority to set enforcement priorities on immigration law just as he does on criminal law, especially since the violations far overwhelm the resources available to prosecute them. Those who say he doesn't argue that such systematic en masse relief without Congressional authorization is tantamount to writing laws by executive fiat.

Reason Foundation Senior Analyst Shikha Dalmia will moderate two pre-eminent libertarian constitutional scholars Ilya Shapiro and Ilya Somin as they go toe-to-toe in a live debate on this controversial issue that promises to have major repercussions for the presidential election this year. Shapiro of the Cato Institute will argue that the order goes beyond the president's lawful powers and Somin of George Mason University and Washington Post's Volokh Conspiracy will argue that it fits within the relevant legal and constitutional provisions - and is the right thing to do.