One of the major reasons why those who employ illegal aliens are so supportive of "comprehensive" immigration "reform" is probably to avoid legal penalties. Not those coming from various government forces, since most politicians have been corrupted. Rather, penalties obtained by lawyers in civil suits. Howard Foster is one lawyer who's brought such suits, and another is profiled in the Orange County Register's "Suit contends illegal pickers undercut firm":

An Orange County attorney filed a lawsuit Monday accusing a Kern County farmer of hiring illegal immigrants to undercut his client's contract to provide blueberry pickers during harvest.

The suit on behalf of farm-labor contractor AgriLabor is the first in a series of suits that attorney David Klehm of Anaheim says he has undertaken since quitting his stable job as a medical-malpractice lawyer two months ago to take on California companies that he says skirt immigration law.

Klehm, 42, said his goal isn't to go after undocumented immigrants but rather the employers that make it tough for businesses to compete if they hire workers legally. Klehm, whose office is in Santa Ana, started a Web site in June with help from anti-illegal-immigration activists to reach out to companies that say they are being outbid for jobs or losing work because their legal labor costs are higher...

Sadly, their website uses a flash frontend. On a more entertaining note, "Dane" at FreeRepublic offers this comment on the lawyer:

Great this ambulance chaser puts hospitals out of business, now he sets his sights on Farmer Joe.

UPDATE: Peter Prengaman of the AP has more in "California law used to target businesses using illegal immigrants". On yet another side note, the article is a bit less biased than his previous reports.