PORTLAND, Ore. (AP) - A new study says a crackdown on illegal labor could cost Oregon up to $656 million in tax revenue and 173,500 jobs.

The study was released as the nation awaits a federal court decision on whether employers must verify Social Security numbers for their workers. (Read the full report.)

Oregon State University economics professor William Jaeger says employment would drop 7.7 percent and statewide annual production would fall by $17.7 billion.

Jaeger was commissioned by the Coalition for a Working Oregon, representing 20 Oregon employers that represent more than 300,000 workers in industries such as dairy and nursery.

Jeff Stone of the Oregon Association of Nurseries said Jaeger's findings are significant because bigger economic shock waves could occur in other states, such as California.

(Copyright 2008 by The Associated Press. All Rights Reserved.)