Maybe play the language game? Don't say criminals for starters, it makes you look insensitive to the fact the people who come and stay here do so for a variety of reasons and painting with a wide brush doesn't help.
Sure, if they break a law they are technically criminals but lets put you on the receiving end. A cop stops you for speeding, walks up and calls you a criminal. Most people would be offended. Why? Because they aren't out there hurting people and stealing but by definition they are breaking the law, effectively making them criminals.
My wife's friend is from another country and married to a US service member. Her English is quite decent but raising a kid by herself (he is deployed a lot) and being pregnant, she missed her application deadline by 6 months. Some sort of green car application or extension. Well now she is a criminal, an illegal alien. So take the plans of some of the hardcore right wingers and this woman could be deported and/or denied citizenship. "Welcome home veteran who shed is blood, sweat, and tears, your wife and child can't return to the US!"
Having said that, we are pretty much all criminals.
http://www.amazon.com/exec/obidos/ASIN/B00C7ETC38/?tag=2ahawaii-20You could point out that you are against illegal immigrants of all races. Maybe rephrase the position to "I support individuals who go through the proper procedures to enter and remain in this country"