It was almost impossible for undocumented immigrants.
You don't seem to be documented. You can't work here.
But in 1986, when U.S President Ronald Reagan signed the Immigration Reform and Control Act into law, it actually became impossible.
The Immigration Reform and Control Act made it so that employers were not allowed to hire undocumented immigrants.
Many people who had immigrated here and never got documented couldn't find jobs. They would go home everyday with a sad expression on their face, worried as to if they were gonna be able to provide for their family.
The consequences for employers who hired undocumenented immigrants became a lot more harsh, and the amount of security and attention that there was on the Mexican border increased greatly.