[dirtboy]

If there is no change in how often or where ID's are checked, then the ID will have no benefit for controlling illegal immigration.

It will have one major benefit to controlling illegal immigration - namely, getting a job. Illegals will have a harder time getting bogus IDs.

[palmer]

You are ignoring the fact that illegals get jobs without IDs. The reason is pretty simple, because of unemployment and withholding taxes along with copious paperwork for deducting employee expenses from the business revenue, it is easier and cheaper to hire illegals for cash.