Loophole

There was one way
around the Chinese Exclusion Act and enter America: if any Chinese could
prove their citizenship through paternal lineage, they would be allowed
to enter the United States. For example, if their parents were in the
United States and they could prove it, then they would be allowed entrance.
Many people were indeed ancestors of Chinese Americans, but since the
outbreak of imposters of citizens' children, the laws became much stricter.
These prospective immigrants would buy papers off of the deceased or
children that no longer had a use for the papers, identifying them as
children of American citizens. In those days there was no official document
that could prove such, so interrogations were created to determine whether
or not they were legitimate papers. This was the beginning of the interrogation
process on Angel Island.