 Immigration Acts had previously banned prostitutes, convicts, the insane, and those with serious illness or disability.Nativism changed this through moving toward a racial hierarchy which pitted the superior natives of the United States against the 'inferior' immigrants.Tension between nativists on one side of the debate (who wanted more restriction of immigration) and those that wished to reform existing rules and immigration systems which promoted the inclusion of 'good' immigrants in American society, played a part in the Dillingham Commission's investigation.