They all commit one common crime — They are here illegally.
Almost all of them have committed at least 2 crimes.
1. If they are working and taxes are being taken out, then they are using a stolen/fake SSN, and thus breaking the law.
2. If they are working, and not paying taxes, they are evading taxes, thus breaking the law.
3. If they are not working, then they are receiving some kind of welfare benefits illegally from the govt, thus breaking the law.
Exactly 100% are criminals. The first illegal entry is a misdemeanor. If they are deported and the enter again illegally, it is a felony.