Opponents of mandatory E-Verify argue that the adoption of this measure would not encourage illegal aliens to return to their home countries; it would simply drive them into the underground economy. Their argument ignores evidence that the contraction of jobs available to illegal aliens – first as a result of belated worksite enforcement efforts by the Bush Administration and then the recession – convinced substantial numbers of illegal aliens to return home.

This argument also ignores the fact that about half of the illegal alien workforce is already in the underground economy, i.e., working for cash, and having no taxes withheld from their incomes.

So what about the other half? These are the illegal alien workers who are in the jobs most wanted by unemployed U.S. workers. Even if we buy the assumption that the illegal workers currently in those jobs would remain here and join the underground economy, the benefit of opening these jobs to unemployed Americans would more than justify making E-Verify mandatory.

Now, let’s focus then on the 3 to 4 million illegal alien workers already in the underground economy (plus others who may look for similar jobs when the E-Verify system denies them legitimate work). These jobs are often in sweat shops or casual labor jobs. Those standing at major intersections selling flowers, festooning your doorknob with take-out menus, or other marginal economic activity are examples. These are not jobs that we want to preserve.

The adoption of E-Verify would remove the guise of innocence by which employers currently claim they did not know a worker they hired was an illegal alien. If they don’t use E-Verify, or ignored the result, they would face heavy fines and possible imprisonment. That is likely to eventually eradicate many of those underground economy jobs. Without the jobs that attract illegal immigration, the country would have a better opportunity to get control of its borders, and unemployed illegal aliens would increasingly recognize the need to pack up and return to their home countries.