“The bill requires all private construction employers statewide to run new hires through a federal E-Verify system, an electronic database that checks the legal work-status of new hires by comparing the employees’ information to that of the Social Security Administration and federal immigration officials. More than 20 states have mandated the use of E-Verify in some or all industries.”

https://www.pghcitypaper.com/pittsburgh/whats-really-behind-the-creation-of-pennsylvanias-new-e-verify-law/Content?oid=16127241