During the mid-1880's, anti-Chinese violence reached a peak in the western United States. The Chinese government attempted to protect resident Chinese by urging private individuals to bring criminal suit in federal court on the basis of Section 5519 of the Revised Statutes of the United States. Although Section 5519 had been declared unconstitutional in 'United States' v. 'Harris' in 1882, it was argued on the basis of statutory separability or severality that it remained constitutional in the case of the Chinese. In 'Baldwin' v. 'Franks' (1887), the Supreme Court rejected the separability argument but implied that Congress did have the power to legislate to protect the civil rights of foreign residents.
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