Através da aplicação de Lei de Rappaport

Rappaport’s Law enforced strict segregation between the No-Maj and wizarding communities. Wizards were no longer allowed to befriend or marry No-Majs. Penalties for fraternising with No-Majs were harsh. Communication with No-Majs was limited to that necessary to perform daily activities.

Rappaport’s Law further entrenched the major cultural difference between the American wizarding community and that of Europe. In the Old World, there had always been a degree of covert cooperation and communication between No-Maj governments and their magical counterparts. In America, MACUSA acted totally independently of the No-Maj government. In Europe, witches and wizards married and were friends with No-Majs; in America, No-Majs were increasingly regarded as the enemy. In short, Rappaport’s Law drove the American wizarding community, already dealing with an unusually suspicious No-Maj population, still deeper underground.

Assim como qualquer trouxa Nenhuma lei Maj, eles esperam que a própria lei impeça que a maioria das bruxas e bruxos a quebre. Considerando que a população bruxa realmente não é tão grande (como uma porcentagem da população total), provavelmente não é tão difícil para os aurores americanos realizar inspeções aleatórias.

Isso impediria todos os casamentos entre os No-Majs e os Wizards? Provavelmente não, mas aqueles que infringiram a lei teriam que viver em reclusão e com medo de que fossem descobertos.