The only thing that makes anybody an illegal alien in the US is, when he doesn't properly defend against the accusation that he is an illegal alien.
Stand as a man/woman in court, unrepresented by anyone, even yourself, and maintain the continual question for the judge, prosecutor, and anyone else accusing, "I, man/woman,
'named', require that you show me the harm or damage you think I did to you, and prove that I was the one who did it, with at least one other witness besides yourself."
They can't answer this point, except if the man/woman did damage or harm to the judge, prosecutor, accuser... that can be shown and proven.
If that is your stance throughout court, no matter who you are, you win, except if you did harm or damage that they can show and prove. Why? Because once you are in, you are in. You are no longer an illegal alien. US and State law apply to you.
If they catch you right on the border, and don't immediately repel you back into whatever country you were crossing the border from, but rather drag you into their holding pen, you are in. You might be termed an illegal alien. But as long as you maintain that you are a man/woman only, unrepresented, and requiring that they show what harm or damage you did, you are in.
If the judge or prosecutor ignore your stance, you have the right and duty to file a court case against them requiring an answer to your question of harm or damage, and to sue them if they hinder your right to travel that is protected by the 1st Amendment, when harm or damage isn't shown.