So, I think I should share with some of you here who may be confused on things because you've never had a run-in with the law before.
In order to get punished for committing a crime, a series of events have to happen, something like this:
1. A crime must be committed.
2. Someone other than the criminal must witness the crime.
3. The crime must be reported to the authorities OR law enforcement must have probable cause to believe a crime has been committed and that you are the criminal.
4. The authorities must investigate and find evidence and witnesses. This is where people get arrested, questioned, and search warrants are executed.
5. The prosecutor must put together a case and bring it before a Grand Jury.
6. The Grand Jury must decide that the case is likely to win and go forward.
7. The criminal must be brought in and charged with a crime. The judge must find that there is probable cause and that the accused pleads innocent. (ALWAYS plead innocent, even if you KNOW you did it and they have all the evidence.) If the accused pleads guilty -- it goes to sentencing.
8. A trial is held with a jury. Lawyers from the prosecution argue with lawyers from the defense about what is evidence, which witnesses are believable, and what the facts together say.
9. The jury must find you guilty.
10. The judge must sentence you.
THEN AND ONLY THEN do you get punished for a crime in the US.
NOW, you may have heard "the process is the punishment". The process is not fun but if you pretend to be a good little boy things go a lot easier. IE, if the police try to arrest you, just let them arrest you. You can complain to your lawyer later, and if they broke the law by arresting you, you can sue them for damages and it's pretty much a slam-dunk win.
MOST CASES do not go to trial. They don't even go to a grand jury. Typically the prosecutor meets with the accused and offers a plea deal. NEVER TAKE A PLEA DEAL. Talk with your lawyer carefully about the plea deal and realize that the best bet is to have all the facts come out in the case and have the jury either find you not guilty or have the judge decide you are a good little boy and don't deserve the maximum punishment. Your lawyer should tell you what plea deal is good or not, and whether it's wise to take it. More often than not it is not wise.
FINALLY -- what Trump is doing with illegals is this. It's pretty awesome.
1. The government has some evidence of some sort that so-and-so is here illegally.
2. They arrest the individual and deport him. No trial since the illegal is not subject to the jurisdiction of any US court.
Now, obviously, you might be wondering what you do if you are not in the country illegally but get deported. It's really simple. You contact a lawyer, and they ring up a judge in the US who exercises "habeas corpus" and gets you out of jail or wherever. The judge can look at the evidence of whether you are here legally or not and make a decision. But until the judge figures out whether you are here legally or not, the government can put you in a holding cell or whatever, or even tell you to stay in the country you were deported to.
What's super-duper nice about the laws at the federal level is that certain kinds of people do NOT get a second chance with habeas corpus. For instance, terrorists and such. A judge can't say "habeas corpus" and summon you back to America if you are on a terrorist list. It just can't happen.
So you might be wondering why there are so many illegals in the US and how Biden got them in. It's simple. They are not here "illegally", they are supposedly claiming asylum, and rather than send them home to wait for their asylum hearing, Biden said they could stay in the US. Well, Trump has ordered all of them to leave, they are no longer welcome to wait in the US for their asylum hearing. In fact, he resurrected an old law on the books that requires illegals to register with the government at their nearest post office. If they don't, it's automatic deportation. If they do, it's still deportation.