Many commentators and blogs have noted the need to punish employers for hiring illegal immigrants with more than slaps on the wrists (if that). It has to become financially harmful (or at least not beneficial) to hire illegals.
As the federal government is reluctant to enforce the law, legislation that allows illegals to sue their employers for abuse, lack of insurance, etc. may be useful. I don't know if this is possible currently, but if so it might be benficial to encourage such lawsuits. It should be made clear that illegals will not be free from deportation and that they may not sue the government for welfare, social security, etc., but that if they prove their case they may receive millions of dollars. They can go back to Mexico and live like kings. Creating a class of employees who become known as letigious will help make employers think twice. A few highly publicized cases can show what employers face.