100% of illegal immigrants *are* criminals.

Crimes for Which Migrants are Prosecuted

Physical presence in the United States without proper authorization is a civil violation, rather than a criminal offense. This means that the Department of Homeland Security (DHS) can place a person in removal (deportation) proceedings and can require payment of a fine, but the federal government cannot charge the person with a criminal offense unless they have previously been ordered deported and reentered in violation of that deportation order. Likewise, a person who enters the United States on a valid visa and stays longer than permitted may be put in removal proceedings but cannot face federal criminal charges based solely on this civil infraction. Those who enter or reenter the United States without permission, however, can face criminal charges.

americanimmigrationcouncil.org - Immigration prosecutions
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Illegal entry into the United States occurs when an individual enters without proper authorization, which includes crossing the U.S. border at non-designated points or using fraudulent documentation to gain entry. This act carries serious legal ramifications and is considered a federal misdemeanor for the first offense.

novo-legal.com - Visa overstays vs illegal entry