A friend of mine and I came up with what we think is a foolproof three step way of minimizing illegal immigration from Mexico and Central/South America. The illegals who come to the US for the money.
First, enforce the use of e-verify. Secondly, put long teeth in the sanctions part. The big house ain't no fun.
Thirdly, enact a "prime contractor" law. I'm not sure the US has ever had this kind of law and maybe you are familiar with it under another name, but essentially it means that the guy (since corporations are people, and that was a gender-neutral "guy") who ultimately pays the tab is responsible for the actions of his sub-contractors.
So when WalMart is busted for illegal workers on their subcontracted janitorial staff it is Doug McMillon who is perp-walked past the press photographers. And put long teeth in the sanctions there too. No longer can they claim "well, I insisted that the workers be legal, it was the subcontracting company that is to blame".
The jobs dry up, the illegals go home and new ones don't come.
I saw this firsthand in the oil industry in Alberta. A company would go out to bid on some service and Joe would bid $X, Fred would bid $1.05X, Steve would bid $0.95X and Luigi would bid $0.75X. So the greedy company chooses Luigi and you don't become the boss of a company without knowing that there has to be something wonky in a bid that low, some corners are being cut.
In the Alberta oilpatch, it wasn't illegal workers, it was usually not following safety or environmental guidelines, but the same principle applied. Since they passed the prime contractor law, safety and environmental compliance is up, injuries and environmental damage are down.
And a heartfelt apology to all Italians the world over, but the stereotype was just too tempting.