What Is Considered An Illegal Activity Under Immigration Law?
According to the U.S. Department of Homeland Security the following incomplete list are some examples of the most common violations of United States Immigration laws:
Filing false statements on applications or petitions.
Making a false claim that you are a United States citizen.
Making, altering or using counterfeit immigration documents.
Making, altering or using counterfeit documents to support immigration applications or petitions.
Failing to report the arrival of illegal aliens.
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http://www.illegalaliens.us/law.htm