The Seattle Times on the effect of illegal labor on prices, from last year.

Low-paid illegal work force has little impact on prices
By Drew DeSilver

Seattle Times business reporter

More than 7 million illegal immigrants work in the United States. They build houses, pick crops, slaughter cattle, stitch clothes, mow lawns, clean hotel rooms, cook restaurant meals and wash the dishes that come back.

You might assume that the plentiful supply of low-wage illegal workers would translate into significantly lower prices for the goods and services they produce. In fact, their impact on consumer prices — call it the “illegal-worker discount” — is surprisingly small.
The bag of Washington state apples you bought last weekend? Probably a few cents cheaper than it otherwise would have been, economists estimate. That steak dinner at a downtown restaurant? Maybe a buck off. Your new house in Subdivision Estates? Hard to say, but perhaps a few thousand dollars less expensive.
The underlying reason, economists say, is that for most goods the labor — whether legal or illegal, native- or foreign-born — represents only a sliver of the retail price….THE REST HERE.
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