I hate how everyone overlooks the fact that most "illegal immigrants" are committing a civil offense that is not supposed to allow for any detainment like a criminal offense. And the criminal offenses that are mentioned in the study are mostly state offenses that are supposed to be handled by state law enforcement. There are a very small number of people who have actually committed federal criminal offenses that justify any detainment at all by ICE.
Wait- are you seriously arguing that everyone in the country illegally CAN'T be detained? That illegals are required to remain free, and stay illegally as long as they want?
That's a border control policy known as "no border control at all".
Overstaying a visa, which is the most common way to be "illegal" is literally not a crime and is not handled by criminal courts in the US. It is strictly a civil matter handled by civil courts (which can't impose jail time, by definition.) Sneaking into the country is a federal crime (a misdemeanor for the first offense and a felony for the second) and is handled by criminal courts.
I would rather no border control at all than a secret nazi-like police who are loyal only to their dear leader. We have law and order. There is a proper way to do things. Only fools think dismantling the system will work to their advantage.
If they enter it illegally, that's probably a crime (I have no idea of what it's like in the US).
Of course visa violations aren't a crime, did you ever had to fill administrative papers? What if misfiling your taxes was a crime, regardless of intent? Do you want everyone who made a mistake on their taxes to go to prison preventively? Or only fraudsters?