On “Up With Chris Hayes” Sunday, the show’s titular host challenged one of the architects of Arizona’s tough immigration law to convince him and his viewers that the law is not, as critics contend, steeped in racism.

“You need to convince me and convince folks on the other side that this is not motivated by racial animus,” Hayes told Kansas Secretary of State Kris Kobach, who, as an immigration reform lawyer, helped draft Arizona’s controversial measure.

Kobach defended the law, and took personal umbrage with it being characterized as a racially-motivated policy.

“It oversimplifies things, and I think it is an ad hominem attack when you say to someone who’s making a reasonable argument, ‘Oh, you must be all about race,’” Kobach said.